Gas Desorption from Detonation Nanodiamonds ...

Chapter 6

Gas Desorption from Detonation Nanodiamonds During TemperatureProgrammed Pyrolysis A. P. Koscheev Karpov Institute of Physical Chemistry, ul. Vorontsovo pole 10, Moscow, 105064, Russia [email protected]Ĭi.ac.ru

6.1 Introduction One type of carbon nanomaterial, the so-called ultradispersed detonation diamond (UDD), can be synthesized by detonation of explosives in closed volumes under an inert atmosphere, followed by subsequent chemical treatments of detonation carbon soot to remove impurities and non-diamond forms of carbon [1, 2]. UDD is an interesting object for investigations from many point of view, such as the production methodology (utilization of explosives), the nanostructure of the UDD particles (crystal mean size is in the range 3–6 nm with narrow size distribution) and the several novel technological applications of UDD [3, 4]. Current and potential applications of UDD cover wide fields starting from lubricants, polishing pastes and galvanic coatings [3], through polymer composites [5–7], sorbents [8–10] and catalysts [11, 12] to biolabeling [13], drug delivery [14], medical tomography [15] and implants [16] in biomedicine (see recent reviews in this field [17–19]). Carbon Nanomaterials for Gas Adsorp on Edited by Maria Terranova, Silvia Orlanducci, and Marco Rossi Copyright © 2012 Pan Stanford Publishing Pte. Ltd. ISBN 978-981-4316-48-9 (Hardback), 978-981-4364-19-5 (eBook) www.panstanford.com

220

Gas Desorption from Detonation Nanodiamonds

The existing synthesis technology allows the production of UDD on an industrial scale (tons per year). UDD powders are produced commercially in several centers in Russia, Ukraine, Byelorussia, Bulgaria, China, and Japan. The technology of UDD production consists of two steps: detonation synthesis of diamond-carbon soot and post-synthesis chemical purification. The main range of UDD particle sizes (some nanometers) depends only slightly on the technological details of production [1, 20, 21]. It is interesting to note that nanodiamond particles of similar sizes were found in meteorites [22] and are believed to belong to the family of “presolar dust grains” formed during star explosions [23]. This “invariance” of nanodiamond particle size was theoretically investigated using the model of carbon clustering and diamond/graphite transition in detonation regime [24]. Due to the small sizes of UDD particles the surface may be covered by a variety of O-, H-, N-containing functional groups (up to 20% by weight) with different chemical composition and structure [25]. In fact, an UDD nanoparticle should be considered as an inert diamond core covered by the chemically active shell of complex nature. In contrast to particle size, the surface chemistry of UDD strongly depends on the details of production technology [26]. The stage of chemical purification, which can vary from producer to producer, is the main factor governing the formation of specific chemical properties of UDD surface [27–30]. The nature and content of surface functional groups and hence the chemical activity of UDD are specifically dependent on the production method. From this point of view, the nanoproducts offered by different producers sunder the global name “detonation nanodiamonds” should be considered as different materials. Our experience indicates that the surface chemistry of UDD samples from even the same trademark can be different due to uncontrolled variation in the details of synthesis technology. This difference can lead to the lack of reproducibility and must be taken into consideration for the technological applications of as received UDD. To decrease the polyfunctional character of the surface of asreceived UDD and to obtain predominantly monofunctional surface layers, the UDD is subjected to chemical treatment (fluorination [31, 32], chlorination [33, 34], hydrogenation [35, 36], and others [37]). The key feature of UDD is the possibility to functionalize the surface by introducing specific chemical groups, including the

A Short Survey of Applications of Thermal Desorption Mass Spectrometry

grafting of different organic functionalities, in order to modify the chemical activity of UDD in a way suitable for their subsequent practical applications (see reviews [19, 38]). The great importance of surface chemistry of UDD requires a deep investigation of the properties of functional groups, both at the stage of production and after subsequent chemical modification. Characterization of surface groups on UDD is usually achieved by Fourier transform infrared (FTIR) spectroscopy [25, 27, 29, 30, 34, 35], because diamond is transparent in IR-region and the IR-spectra of UDD are mainly produced by surface species. X-ray photoelectron spectroscopy (XPS) was also used for this purpose [31, 39, 40]. The main disadvantages of these methods are the relatively low sensitivity and difficulties in data interpretation to obtain direct information on the chemical composition of surface groups. The mass spectrometry analysis of chemical composition of gases evolved from the solid sample during programmed heating in vacuum or in inert atmosphere, so-called thermal desorption mass spectrometry (TDMS), is a technique providing information on the chemical composition and the thermal stability of surface species. TDMS was widely used to study the surface chemistry of dispersed carbon materials [41, 42], diamond monocrystals [43] and diamond powders [44]. TDMS seems to be a promising technique for characterization of UDD surface as well [26].

6.2 A Short Survey of Applications of Thermal Desorption Mass Spectrometry to the Study of the Surface of Diamond Materials TDMS is a method of characterizing the surface species by programmed heating of the sample under vacuum and simultaneously detecting of the evolved gas by means of a mass spectrometer. During the temperature increase some adsorbed species and decomposition products of surface functional groups escape from the surface at different temperatures causing a rise in the pressure of a specific mass component. The results of measurements usually are represented in the form of temperature profiles (spectra of thermal desorption) of ionic fragments with different masses in the mass spectrum. This method is characterized by high sensitivity and high information content. Besides the information about the chemical composition of

221

222


surface compounds and their relative amounts, the method allows to determine the temperature dependence of desorption rates, the thermal stability of surface groups, and the activation energy of corresponding processes. Several types of C–O and C–H bonds were found by TDMS on the surface of the diamond monocrystals after interaction of oxygen [44], hydrogen, and water vapor [45] with the diamond powders at elevated temperatures. Later, this method was applied to the study of the surface of diamond powders modified by oxidation [46], hydrogenations [47], or other treatments [48–50]. The high sensitivity of the method provided the feasibility to study the adsorption of oxygen [43], hydrogen [51], and other molecules [52–54] even on the surface of a single crystal of diamond. The obtained results allowed to establish the presence, in particular, of a variety of oxygen-containing functional groups, such as carbonyl (C=O), lactone [(C=O)O], carboxylic acid [(C=O)OH], cyclic ether (COC), and carboxylic anhydride [(C=O)O(C=O)] on the diamond surfaces. These groups differ by thermal stability and are decomposed with the formation of CO and/or CO2 at different temperatures [46, 47]. Only limited information, mostly of fragmentary nature, is available on the application of the TDMS for characterization of UDD surfaces. A substantial variation of the composition of the desorption products (hydrocarbons, chlorine- and sulfur-containing compounds) in vacuum at temperatures up to 400°C has been found for UDD samples purified by different procedures [28]. Some transformations of oxygen-containing groups were detected by TDMS for UDD heated in air, nitrogen, and hydrogen (temperature profiles of CO and CO2 up to 850oC) [55]. A complex form of the temperature profile for water desorption from UDD surface has been evidenced in the temperature range up to 800°C [56]. The effect of chemical treatment of UDD on the spectra of thermal desorption of H2O, HCl, and oxygen at temperatures up to 600°C has also been noted [57]. It has been shown by means of TDMS in a wide range of temperatures (up to 1100°C) that H2O (100–600°C), CO2 (200–600°C), CO (500–900°C), and H2 (above 800°C) along with some traces of hydrocarbons were the main products of thermal desorption from the different types of UDD used as analogs of meteoritic diamonds [58]. Similar results have been described in relation to the problem of UDD graphitization [59].

Results of the Studies of Detonation Nanodiamonds of Different Types

What follows is a brief summary of the results of detailed TDMS studies performed on UDD synthesized in different scientific centers. All measurements were carried out under the same protocol in order to ensure the possibility of quantitative comparisons. We were trying to answer the following two key questions: (i) what are the “fingerprints” left in UDD by different producers (certification), (ii) is it possible to erase the “chemical memory” about the origin of UDD (unification). Some results of the works were published in the form of abstracts and regular papers [26, 58, 60–65].

6.3 Results of the Studies of Detonation Nanodiamonds of Different Types 6.3.1 Objects and Methods A number of UDD powders, produced by different scientific centers, were used in this comparative study of their surface chemistry. All samples were synthesized by the detonation of a mixture of trinitrotoluene (TNT) and 1, 3, 5-trinitro-1, 3, 5-s-triazine (RDX) as primary step. The samples used in this work differ in the details of both the detonation synthesis and the chemical separation procedure [26]. The powders have different colors, changing from brown to light gray, depending on the UDD type. Also, the sedimentation stability of aqueous colloidal solutions of UDD, an important factor for some practical applications of UDD [66], was found to depend strongly on nanodiamond type [26]. In some cases a total precipitation occurred in few hours, for some samples the colloidal solution remained stable during months [26]. The structure and chemical composition of as-received samples of different types of UDD were characterized by means of X-ray diffraction, IR and Raman spectroscopy, elemental analysis, thermogravimetry, and TDMS.

6.3.2 Structure, Chemical Composition and Thermal

Stability of Various UDD The X-ray diffraction analysis did not reveal noticeable differences between crystal structures of the samples. The X-ray diffraction patterns were similar to those observed in Ref. [67] and contained

223

224


the broad diffraction lines of the cubic lattice of diamond with average crystallite size of 3–5 nm.

Figure 6.1 Raman spectra of various carbon materials. (1) UDD K-2; (2) UDD CH-7; (3) natural diamond; and (4) pyrolytic graphite. Excitation wavelength—514 nm.

The main features of Raman spectra were similar for UDD of different types as shown in Fig. 6.1, where the spectra of natural diamond and pyrolytic graphite are reported for comparison. The diamond sp3-line in the Raman spectra is broadened (FWHW = 30–40 cm–1) and shifted to 1325 cm–1 in comparison with the characteristic Raman peak of natural diamond (1332 cm–1). This behavior is typical of the nanodiamonds [67–69]. An additional broad asymmetric band near 1600 cm–1 (FWHW ~ 100 cm–1), assigned to graphitic sp2-bonded carbon (G-peak) in the nanodiamonds [67, 68] is also observed in the Raman spectra. UDD samples of different origin were somewhat distinguished by the ratio of the intensities of the diamond and graphite Raman peaks. The data of thermal analysis did not show essential differences as regards the

Results of the Studies of Detona on Nanodiamonds of Different Types

oxidation processes of nanodiamonds of different types. Noticeable oxidation with mass loss begins at temperatures of 430–450°C; the maximum is reached in the temperature range 520–560°C. The specific surface area of nanodiamond powders (280–320 m2 g–1) only slightly depends on the type of nanodiamonds [26]. The main differences among UDD of different types are the nature of surface impurities and the structure of functional surface groups. Elemental analysis (for M > 27) of nanodiamonds showed the presence of Fe, Cr, Si, Ca, Cl, and S with different abundance of the order of 10−1 wt.%, strongly depending on the UDD types [26]. These impurities are introduced mainly at the stage of the chemical procedures for diamond extraction from detonation soot. The whole surface concentration of these impurities in UDD particle with the mean size of ~4 nm does not exceed 0.05 monolayer, at least an order of magnitude lower than the concentration of surface functional groups. A clear difference was observed also in the amounts of the volatile products released in vacuum from samples heated to 1100°C (the onset of intensive graphitization of nanodiamond [3, 59]). It was established that the evolved gas volume (per sample mass unit) can vary by a factor two for the different samples of UDD with approximately the same specific surface area [26]. The mass loss of UDD heated up to 1100°C in vacuum can reach 20–25% for some samples. This result indicates that almost the whole surface of UDD particle is covered by chemical functionalities forming volatile products under heating. No distinct correlation was found between the sedimentation stability of UDD colloids on one hand and both concentrations of trace impurities and whole amounts of volatile products on the other hand [26]. Some properties of investigated UDD samples are summarized in Table 6.1.

6.3.3 FTIR Spectroscopy of UDD of Different Types The high transparency of diamond in the infrared spectral range and the high surface-to-volume aspect ratio of UDD allow to study the surface chemistry of UDD using the IR-spectroscopy. The FTIR spectra of as-received UDD powders of five different types, measured in the diffuse reflection mode, are shown in Fig. 6.2. Different UDD samples exhibit the following IR features similar to those observed

225

226


in numerous studies of UDD [25, 28, 29, 34, 35, 55]. The broad absorption band with the peak near 3400 cm−1 and the peak at 1630 cm−1 are assigned to the hydroxyl groups. These bands result mainly from water molecules adsorbed from the ambient atmosphere, as they can be reversibly diminished by simple evacuation of UDD samples under heating to 100–200°C [56, 66]. The features near 2900 cm–1 are due to C–H vibrations. The peak in the region 1720– 1850 cm−1 is related to C–O vibration in oxygen-containing groups with various configurations. The complex absorption band in the range 1400–900 cm–1 is the superposition of absorption peaks due to nitrogen centers in diamond lattice, CO–, CH–, OH– groups, etc. Table 6.1

Some properties of UDD of different types used in the work

Sample1

(Producer)

Detonation media; Main purification impurities2 agents (%)

CH-7 (Research Institute of Technical Physics, Russia)

Ice CrO3 H2SO4

Cr (0, 32) Si (0, 21) Fe S

S-1 (Research Institute of Technical Physics, Russia)

Ice Ozone

Si (0, 08) S (0, 04) Fe (0, 06)

K-2 (Krasnoyarsk State University)

Carbon dioxide В2О3 HClO4

Ca (0, 55) Fe (0, 16) Cl (0, 07) B

Specific Volatile Sedimentation surface3 abundance4 stability in (m2/g) rel. units water5 310

290

1, 0

High

2, 2

Very high

2, 0

High

2, 1

Low

В-1 Carbon (Sci. Manuf. Co. dioxide “Altai”) HNO3, H2SO4

S (0, 4) Fe (0, 38) Ca (0, 1) Si (0, 03)

А-1 (Research Institute of Experimental Physics, Russia)

Water Mineral acids + HF

Cl (0, 9) Fe (0, 15) S (0, 06)

225–275*

1, 2

Medium

А-2 (Research Institute of Experimental Physics, Russia)

Water CrO3 H2SO4

Si (0, 27) S (0, 25) Cl (0, 18) Cr

225–275*

0, 9

Very low


G-1 (PlasmaChem, Germany)

Carbon dioxide Unknown

Ca (0, 41) Fe (0, 25) Si (0, 28) Cl (0, 06)

2, 1

High

1Type

of sample (tentative names). by X-ray dispersion analysis and secondary ion mass spectrometry. 3Measured by thermal desorption of nitrogen (*data of the producers). 4Total amount of volatiles released under the heating up to 1100°C in vacuum. 5Estimated using the kinetics of optical transmission of water suspension of UDD (0.02%). 2Determined

ABSORBANCE

5

4

3 2

1 4000

3500

3000

2500

2000

1500

1000

W AVENUMBER (cm -1)

Figure 6.2 FTIR spectra of detonation nanodiamonds of different types. (1) G-1; (2) CH-7; (3) K-2; (4) B-1; and (5) S-1.

The details of IR spectra taken from the UDD samples are strongly dependent on the type of UDD (Fig. 6.2). Besides the shape of the complex band in the 1400–900 cm–1 region, the main differences are in the intensity of C–H vibrations (near 2900 cm–1), and, what is more important, in the position of the characteristic line of C–O groups located between 1720 cm–1 (sample CH-7) and 1850 cm–1 (sample S-1). The last observation indicates a substantial difference in the structure of the CO-containing species, including carbonyl, lactone, and acid anhydride groups [46], on the surface of UDD from different producers. Though the interpretation of infrared spectra details of UDD is rather speculative and ambiguous, IR spectroscopy is widely used to characterize the surface chemistry of UDD due to relative simplicity of measurement procedure. In a first approximation, FTIR spectroscopy could be considered as a rapid method to obtain the “finger prints” of UDD of different origin.

227

228


6.3.4 Main Features of Thermal Desorption of Gases from UDD The TDMS spectra were recorded using quadruple mass spectrometer in the range of mass numbers from 2 to 100 amu during programmed heating of UDD aliquots (1–2 mg) at a rate 13°C/min up to 1100°C in vacuum. The released gases were continuously pumped at a rate of about 1 l/s (relative to nitrogen). In this way the measured partial pressures of gases were proportional to desorption rates at every moment. The obtained mass spectra (more than 100) were analyzed and handled by means of special software to calculate the intensities of characteristic ion fragments at different temperatures, their temperature profiles, and the relative amounts of released species. Identifications of the chemical composition of desorbed gases were performed using MS library (National Institute of Standards and Technology (NIST)).

Figure 6.3 Thermal release of the main gases from UDD of types G-1 and B-1.

A variety of species were found to be desorbed from UDD under heating in vacuum. The TPD curves shown for some of these species in Fig. 6.3 indicate that the processes of decomposition of different surface groups are separated on a temperature scale. For


all investigated UDD the main products of desorption were H2O (100–600°C), CO2 (200–600°C), CO (500–1100°C), and H2 (above 800°C), as shown in Fig. 6.3 for two different samples. In some cases traces of hydrocarbons (200–400°C), HCN (above 800°C), HCl, and SO2 (400–600°C) were also observed (not shown in Fig. 6.3). Some features of thermal desorption of H2O, CO, and CO2 are presented in Table 6.2. Table 6.2

Total amounts (in relative units) and temperature peaks (shown in parenthesis) of H2O, CO, and CO2 desorbed from UDD of different types under heating up to 1100°C

CH-7

S-1

K-2

B-1

A-1

H2O

1.21 0.72 1.06 1.48 (360, 580) (140, 370) (130, 480) (215)

0.59 (360)

CO

3.22 (340, 710)

7.46 (475)

3.43 (640)

CO2

1.06 (330, 480)

3.65 (440)

9.32 6.95 (580, 840, (710) 1000) 1.96 (550)

A-2

G-1

1.03 1.07 (350, 590) (140, 480) 2.20 (740)

2.23 1.35 0.6 (430) (450–550) (400–600)

8.7 (600, 800, 1030) 1.94 (540)

The difference between the investigated samples consists, first of all, in the CO and CO2 contents and in the temperature profiles of desorption of such species. In the general case the spectra of thermal desorption of CO and CO2 (Fig. 6.4) result from the superposition of several desorption peaks with the maxima in the range 300–1000°C. Each peak corresponds to the decomposition of a specific functional group. A more accurate analysis of the profiles of thermal desorption can be performed by the mathematical decomposition into separate Gaussian components [42]. As an example, the profile of thermal desorption of CO from the sample K-2, reported in the insert of Fig. 6.4, is satisfactorily described by the superposition of five bands with maxima near 560, 630, 720, 850, and 1020°C, respectively, and with a half-width of 110–150°C. The trend of CO and CO2 desorption profiles under linear heating of UDD can be explained by the following simplified scheme [46, 42]. The carboxyl groups are decomposed at low temperatures (below 400°C) giving rise to the desorption of CO2. In the range 400–600°C the acid anhydride groups are destroyed with the desorption of both CO and CO2. Noticeable desorption of CO2 observed at 600–700°C can be connected to the decomposition of lactone groups. The

229


high-temperature peaks (above 600°C) of CO desorption are likely generated by decomposition of ester, hydroxyl, and carbonyl groups. A more careful analysis of thermal decomposition of functional external layers should take into account the possible transformation of the oxygen-containing groups on diamond surface under heating. For example, a partial decomposition of anhydride groups can convert them into lactones and carbonyls [46]. 25 20

435

CO 2+

S-1

15

555

10 B-1

5

K-2 A-2

0

CO +

K-2

575

25

475

Desorption rate, arb. u.

20

700 400

S-1

15

B-1

800

1000

o

T, C

1000

K-2

600

840

230

10 5 A-2 0 200

400

600

800

1000

TEMPERATURE, oC

Figure 6.4 Temperature profiles of ion fragments CO+ (m/z = 28) and CO2+ (m/z = 44) in TDMS spectra of UDD samples of different origin. The insert shows the decomposition of real CO-profile (corrected to the contribution of the fragment CO+ from CO2) into the separate Gaussian peaks for UDD K-2.

There is a correlation between the profiles of CO desorption from different samples and their IR spectra (see Fig. 6.2): the higher the wave number of CO band near 1800 cm–1, the lower the temperature of decomposition of the corresponding surface compounds with CO emission. The TDMS method is more sensitive than the IR spectroscopy to reveal the structural features of the functional surface coatings of nanodiamond, as illustrated by the deep difference in the profiles of thermal evolution of CO from the


samples G-1 and K-2 (see Figs. 6.3 and 6.4), whose IR spectra are practically identical. No distinct correlation was found between sedimentation stability of UDD aqueous suspensions (Table 6.2) and the total amount of surface functional groups measured by total gas evolution under pyrolysis of UDD up to 1100°C. It is established, however, that the stability of UDD suspension is higher for the samples with greater total amount of CO and CO2 desorbed in the temperature range of 400–600°C, as a result of the decomposition of acid anhydride and lactone groups. The sedimentation stability of a solution of nanodiamond can be controlled by concentration of acid anhydride and lactone groups that impart acid properties to diamond nanoparticles and negatively charge the particle in aqueous solutions preventing their aggregation [70, 71]. An exception is represented by the sample CH-7, with low level of surface oxidation and high stability of aqueous solution. This sample however is characterized by a high degree of the surface contamination by the hydrocarbon species [62], which can act as surface-active species causing high sedimentation stability for this type of UDD. Thus, the UDDs of different types, synthesized by explosion technology in different conditions and purified using different chemical procedures, are different from each other mainly in terms of concentration and structure of the surface oxygen-containing and other functional groups. These groups are decomposed by vacuum pyrolysis giving rise to the formation of volatile gas component. The temperature profiles of different gases, as shown in Fig. 6.3 can be considered as “fingerprints” of the technology of synthesis and purification of UDD and can be used for the certification of ultradispersed nanodiamonds of different types.

6.3.5 Influence of Additional Acid Treatment on the Surface Chemistry of Nanodiamonds of Different Types The profound effect of the synthesis technology of UDD on their surface chemistry is the cause of the different behavior of UDD in many practical applications. One faces, therefore, the problem of how to unify the surface properties of UDD of different types for the purpose of obtaining “standard” products independently of their origin. One of the possible ways of solving this problem consists

231


in the additional chemical modification of different UDD by means of the same acid treatment, similar to the procedure of extraction of nanodiamonds from detonation soot. The productivity of this approach was checked using UDD samples of different types with widely different initial surface properties. All examined samples were subjected to the identical chemical procedure of nanodiamond extraction, which included treatment in concentrated mineral acids and oxidation by perchloric acid [60]. Chemical properties of functional groups on the surface of UDD were characterized by TDMS method. It was found that chemical treatment caused an increase in the “degree of oxidation” of surface, that was manifested as a shift of the maxima of thermal CO desorption to lower temperatures, as shown in Fig. 6.5 for the samples of two types, and in an increase in the total amounts of carbon oxides desorbed in the range of 400–700°C (twice for K-2 and five-fold for CH-7). CO 2

1

590

535

530

510

1

2 530

560

2

3 0

CO2+ intensity, arb. u.

755

370

560

575

CO

CO+ intensity, arb.u.

232

3 200

400

600

800 1000 0

200

400

600

800 1000

TEMPERATURE, oC

Figure 6.5 Effects of the modifications of UDD K-2 (solid line) and CH-7 (dashed line) on thermal desorption of CO and CO2. (1) Initial samples; (2) after chemical treatment with acids; and (3) after oxidation in the air at 370°C.

At the same time it was found that the acid treatment does not remove completely the difference in the initial properties of the samples. The profiles of the thermal desorption of both CO2 and CO from chemically processed samples of different types remained


substantially different. In particular, the maxima of thermal CO desorption were observed at 530 and 590°C for the chemically treated samples K-2 and CH-7, respectively, and the total quantity of desorbed carbon oxides differed by more than twice for these samples. The difference of the surface chemistry of chemically treated samples of two types was confirmed also by the data of FTIR spectroscopy l [62, 60]. Another important observation was the detection of chlorine desorbed in the form of HCl from chemically treated UDD in the temperature range 400–700°C [62]. Chlorine was likely introduced during treatment by chlorine-containing acids used in chemical treatment. The contents of chlorine in the treated CH-7 and K-2 samples differed by more than order magnitude [62]. This is an evidence of substantially different chemical activities of nanodiamonds of different types. These results indicate that, even though the chemical extraction procedure affects the surface chemistry of synthetic diamond nanograins, there is a distinct “memory” of surface properties behind the origin of UDD. Some surface features of treated UDD are controlled by their initial “biographic” properties. Thus, the unification of surface properties of UDD by additional acid treatment is possible, if at all, only when “severe” and prolonged treatments are performed, and can hardly be used in practice.

6.3.6 Surface Properties of Nanodiamonds Extracted from Detonation Carbon Soot of Different Types Another possible way to obtain the standardized nanodiamond product could be the application of identical procedure of extraction in the production nanodiamond from carbon soot (the primary product of explosion synthesis) of different types. This possibility was checked using two types of diamondcontaining soot, namely, CH7-ST and K2-ST (“raw material” for obtaining nanodiamond CH-7 and K-2, respectively), synthesized by explosion in ice and carbon dioxide atmosphere, respectively. The UDD extraction was performed using a multistage procedure [61], which includes microwave treatments a mixture of acids HCl, HNO 3, and HF, washing in solutions of AlCl3 and HCl, colloidal separation into H2O/CH2Cl2. The high efficiency of this procedure was confirmed by the experiments of extraction of nanodiamond from meteorites [72].

233


CH7-ST

H 2O +

2

CO +

1

RELEASE RATE, arb.u.

234

CO 2+ 0

CO 2+

6

K2-ST

CO +

4

2

0

H 2O +

0

200

400

600

800

1000

o

TEMPERATURE, C

Figure 6.6 Temperature profiles of the main gas components released from detonation soot of two different types: CH7-ST and K2-ST.

TDMS study of as-received soot samples showed the release of H2O, CO2, and CO as main components, as indicated in Fig. 6.6. In addition some hydrocarbons were released in the temperature range 200–500°C. H2 and HCN started to be released at high temperature above 900°C. Both the rates of release and the shapes of the temperature profiles of different components were found to depend strongly on the type of the soot. As a rule the TDMS profiles consisted of several peaks and shoulders (Fig. 6.6) accounting for the decomposition of different surface species on the soot grains. The positions and the intensities of these peaks are quite different for different soot samples. The total amount of volatiles released during pyrolysis of compounds on the surface of sample K2-ST is higher than in the case of CH7-ST. These results indicate that the structure and the composition of surface species formed in diamond-containing


soot during detonation synthesis strongly depend on conditions developed during the process. Compared with the case of soot samples (Fig. 6.6), the TDMS profiles for the extracted nanodiamonds were substantially modified (Fig. 6.7). The main components released from nanodiamonds were CO (500–700°C) and CO2 (200–600°C) both arising from the decomposition of surface oxide groups, and HCl (bimodal at 400–700°C), arising from surfaces contaminated by chlorine used during chemical extraction. The results indicate a pronounced difference between surface chemistry of different nanodiamonds, clearly illustrated by the curves of the ratio between the release rates of the various species (Fig. 6.7). The whole amount of released COx is higher in the case of K2-Diam in accordance with the data for pristine soot (Fig. 6.6). In contrast, the abundance of chlorinecontaining species is highest for CH7-Diam in agreement with our previous data on chemically treated nanodiamonds CH7 and K2 (see above). What is more important, the shapes of the ratio curves in Fig. 6.7 (the ratio between release rate from K-2-Diam and CH7-Diam), consisting of several peaks and shoulders, indicate that the relative abundances of different surface oxide groups (carboxylic anhydride, lactone, and carbonyl) decomposed at different temperatures are not identical for the two types of extracted diamonds. The same is valid for the chlorine-containing groups. 8

RELEASE RATE (arb. units)

6

Ch7-Diam

HCl+

4 2

CO +

CO 2 +

0 K2-Diam

CO +

12 8

CO 2 +

4

HCl+

RATE RATIO

0 6

CO +

3 0

Ratio

CO 2 +

HCl+

200

400

600

800

1000

TEMPERATURE ( oC)

Figure 6.7 Thermal desorption of CO, CO2, and HCl from nanodiamonds CH7-Diam and K2-Diam extracted from detonation soot CH7ST and K2-ST, respectively.

235

236


The obtained results give strong evidence that the final chemical state of extracted nanodiamond grains depends on the type of raw soot, which in turn differs according to the details of detonation synthesis. This can be caused by the difference in the chemical activity of detonation nanodiamond in carbon soot synthesized in different conditions, which revealed in the reactions with the substances during the extraction from the soot. The chemical activity of the surface of diamond in different media depends on the atomic structure (crystalline orientation) of the surface [73, 74]. The conditions of detonation synthesis have a strong influence on the shape of diamond nanocrystals [75] and the structure of their surface shell [67, 76]. One could suggest therefore to consider the surface crystal structure as a “hereditary” feature affecting the chemical reactivity of nanodiamond surface toward environmental conditions (both during synthesis and extraction). Thus, even with the identical procedure of extraction the surface properties of the final nanodiamond product are in many respects determined by the properties of initial detonation soot, which in turn depend on the conditions of the explosive synthesis.

6.3.7 Modification of Nanodiamond Surface by

Thermal Oxidation As has been demonstrated earlier [58], the thermal treatment of UDDs in air at temperatures up to 450°C is a simple and effective method of modification of the composition and structure of oxygencontaining surface groups. This procedure was applied to the UDD of different types, and the surface chemistry of modified UDD was characterized by TDMS. The TDMS profiles of CO and CO2 for UDD samples CH-7 and K-2 preheated in air at 370°C for 60 minutes are shown in Fig. 6.5 (curve 3). In contrast to the case of acid treatment (Fig. 6.5, curves 1 and 2) the mild oxidation by air oxygen leads to a better “unification” of structure and content of the oxygen-containing groups, revealed by the similarity of the profiles of thermal desorption including the peak temperatures and the amounts of evolved carbon oxides. This possibility of unification of the oxidation state of UDD surface by heat treatment in air was confirmed by the data of IR spectroscopy for the different samples, heated in air atmosphere during 5–10 minutes at 440–460°C [26]. The absorption band of C–O bond is positioned in the range from 1720 cm–1 (sample CH-7) to 1850 cm–1


(sample S-1), and reflects the substantially different structure of the oxygen-containing groups. This signal has practically identical position (1800–1810 cm–1) after thermal oxidation regardless of the type of UDD. The TDMS method can be successfully used for determining the optimum regime (temperature and duration) of thermal oxidation of UDD and for checking the state of the oxidized surface. Figure 6.8 demonstrates the variations of the profiles of thermal desorption of CO and CO2 with the temperature of oxidation in air during 40 minutes for sample CH-7. The noticeable modification of surface (increase in the desorption rate of CO2 and CO near 600°C) is observed at oxidation temperature as low as 300°C (Fig. 6.8, curve 3). The main changes in the desorption profiles occur in the range of 300–400°C. A further rising of oxidation temperature must be avoided because of the possible losses of material (combustion) and the increase in the concentration of nonvolatile impurities (metals, etc.) on the surface due to the combustion of diamond. The thermal oxidation in air seems to be an effective way to unify the surface properties of various UDD and certainly is more environment-friendly than acid treatment or the modification by ozone [39, 40]. The additional advantage of thermal oxidation could be the removal of non-diamond carbon from UDD as shown in Ref. [77]. 565 o

530 o 760

DESORPTION RATE

CO

o

CO 2

5

5

4

4 3

3 2

2

1 0

200

400

600

800 1000

0

200

400

600

1 800 1000 1200

TEMPERATURE, oC

Figure 6.8 Temperature profiles of CO and CO2 release from UDD CH-7 after heating in air at different temperatures: (1) without heating; (2) heating temperature 200°C; (3) 300°C; (4) 400°C; and (5) 450°C.

237

238


6.3.8 TDMS of Gases Released from UDD under High Temperature Pyrolysis: Implication to the Meteori c Nanodiamonds The first publications on the nanodiamond particles found in detonation soot [1, 2] and in some primitive meteorites [22] appeared almost concurrently more than 20 years ago. Meteoritic nanodiamonds (MNDs) contain isotopically distinct noble gas components and are considered as “the messengers from the stars” carrying the traces of nuclear processes in circumstellar media [78]. Some similarities between the properties of UDD and MND (particle sizes, surface chemistry) were pointed out in one of the first paper on UDD [2]. Starting from this similarity we have used UDD as synthetic analogs of presolar diamonds in laboratory simulation experiments of cosmochemical relevance [60–62, 79–83,]. In this section, some results of measurements of noble gases in UDD are presented in comparison with the data on MND.

Figure 6.9 Gas release curves during stepped pyrolysis of meteoritic (Orgueil) nanodiamonds [78] and UDD sample implanted with noble gas mixture (700 eV).


The first study of noble gases implanted into UDD by ion bombardment was performed by mass spectrometric analysis of noble gases released during stepped pyrolysis up to 1600°C [79] using a protocol similar to the one used in studies of the MND [78]. The measured temperature profile of noble gas (He, Ar, Kr, and Xe) released during pyrolysis of UDD has a bimodal character (for Ar, Kr, and Xe) with main peaks in the ranges 200–700 and 1200–1500°C, as shown in Fig. 6.9. The main features of such profiles for all noble gases released from UDD closely resemble those obtained for the diamond residual extracted from Orgueil meteorite [78]. The most striking result is that with a single implantation event we obtain the same doublepeak release pattern found for presolar diamonds. It is to be noted, however, that in the latter case the bimodal character of the curves was attributed to the presence of two distinct components of trapped noble gases, namely, P3-component (isotopically normal) released at low temperatures and HL (exotic) released at high temperatures [78]. Our results clearly showed that both the low-temperature (LT) and the high-temperature (HT) peaks may arise simultaneously in the same substance during “one-component” ion implantation event. It was found in addition that the trapped gases are fractionated favoring the heavy isotopes relative to the starting composition and the fractionalization factor increased with the temperature of the pyrolysis step [79]. The isotope fractionalization factors reached 0.8 (Ar) and 2.5 (Xe) per mass unit at high temperatures. These results provided strong evidence that ion implantation is a viable mechanism for trapping of noble gases by interstellar diamond grains. The observed bimodal character of the release profiles and the isotopic fractionalization during pyrolysis have been used to reconstruct the possible scenario of implantation events in interstellar media [79] and to interpret the noble gas compositions in meteoritic nanodiamonds [83]. The standard procedure of stepped pyrolysis (100oC step as a rule) in the closed vacuum chamber (static mode) is rather time consuming and does not allow to resolve the fine structure of temperature profiles of noble gas release from nanodiamonds. We have therefore developed a new approach based on TDMS method, that allow the continuous measurements of noble gas release during linear heating of nanodiamonds [81].

239


In this case the nanodiamond samples were heated in vacuum at a rate of 7°C/min up to 1600°C. Temperature profiles of evolved noble gases were measured by means of quadruple mass spectrometer. A Ti-getter was used to remove a lot of active gases desorbed during pyrolysis of nanodiamonds, keeping the total pressure of the vacuum chamber below 10−5 torr during the heating runs. The released noble gases were pumped at a low rate through a calibrated orifice. This dynamic mode of operation allowed to measure the evolved active gases as well. This procedure was successfully applied to measure noble gases in UDD and MND [81] and to clarify the mechanism of high temperature release of these gases [82].

HELIUM RELEASE

240

1

2

200

400

600

3

800

1000

1200

1400

1600

o

TEMPERATURE, C Figure 6.10

Temperature profiles of helium release from nanodiamonds. (1) Stepped pyrolysis (static mode) of UDD after implantation of He-ions (700 eV); (2) linear heating (dynamic mode) of the same sample; and (3) linear heating of “presolar” nanodiamonds extracted from Murchison meteorite. The curves are normalized to the maximum intensity.

An example of the release patterns of helium in different nanodiamonds is shown in Fig. 6.10. Please note that, due to small available amount of meteoritic diamonds, only helium could be measured. The temperature profiles of helium from ion implanted UDD measured in static (Fig. 6.10, curve 1) and dynamic (Fig. 6.10,


curve 2) mode were very much alike, confirming the reliability of the latter mode of operation. Similar fine features (peaks and shoulders near 520, 750, 950, and 1150°C) in the release curves were observed for both UDD and MND. This fine structure indicates the presence of different (at least five) states (or processes leading to desorption) of trapped He-atoms in nanodiamonds. The method of TDMS was used to clarify the mechanism of noble gas release from nanodiamond, an important issue for the interpretation of data concerning noble gases in meteoritic diamonds. The curves in Fig. 6.11 represent the results of noble gas analysis in UDD sample after simultaneous implantation of ion mixture (He, Ar, Kr, and Xe) with energy of 1000 eV. The release profiles for the heavier gases (Ar, Kr, and Xe) measured under linear heating have bimodal character (LT an HT peaks) as in the case of stepped pyrolysis (Fig. 6.9). 132Xe

Release rate, rel.scale

84Kr

40Ar

200

Figure 6.11

4He

400

600

800

1000

Temperature, oC

1200

1400

1600

High-resolution temperature-programmed release curves for He–Xe implanted into UDD at 1000 eV.

However, some fine features, such as peaks and shoulders near 550, 700, and 800°C, can be solved in the LT range. This fine structure is similar for Ar, Kr, and Xe. On the other hand, a clear shift of the HTpeak to higher temperatures has been observed in the raw from Ar (1490°C) to Xe (1550°C). The LT-peak of noble gas desorption cannot be caused by thermal decomposition of surface layer as we did not find any correlation

241


between desorption of noble and active gases from UDD having different surface chemistry [62]. We have observed, however, that LT-peak intensity of Xe increased if Xe-ions were implanted into UDD irradiated preliminary by Ar-ions for creation of defects in the diamond core. Hence, the LT-peak of noble gases could be caused by thermal escape of atoms trapped on the defect sites in diamond.

40 Nanodiamond

20

0

84Kr release, arb.u.

242

Carbon soot

20 10 0 Micron sized diamond

20

10

0

Figure 6.12

400

800

1200

Temperature, oC

1600

Implanted Kr (700 eV, ~1014 ion/cm2) release from carbon materials of different structure.

Different type of carbon materials were used in ion implantation experiments to understand the peculiar features of UDD. Figure 6.12


shows the profiles of Kr-release after ion implantation under the same conditions (energy and dose of ions) in UDD, acetylene carbon soot and diamond powder with grain size of ~1 µm. The HT-peak (near 1500°C) appears evident solely in the case of nanostructured diamond, whereas it is characterized by a very low intensity in the cases of micro-sized diamond and non-diamond carbon soot. The HT-peak is somewhat shifted to higher temperatures with increasing mass number of atoms in the raw Ar–Kr–Xe (Fig. 6.11). A similar shift was observed increasing the ion energy, as shown in Fig. 6.12. This shift can reflect the increase of ion penetration depth into diamond crystal with increasing ion energy. One can suggest, therefore, that the difference in the position of HT-peak for different heavy noble gas atoms implanted at the same energies (Fig. 6.11) could be caused by mass dependence of the penetration depth. The calculations performed using the TRIM (transport of ions in matter) mode predict the increase of implantation depth in diamond with increasing ion mass of heavy noble gases (1.3, 1.4, and 1.6 nm for 700 eV ions of Ar, Kr, and Xe, respectively). The following mechanism could be suggested for HT release of noble gases from UDD. The graphitization of UDD under annealing in vacuum occurs at temperatures of the HT-peak (above 1200°C) [84]. Using the data obtained in Refs. [84, 85] we have calculated the temperature dependence of transformed diamond fraction in UDD sample; these data are plotted in Fig. 6.13 (lower part). The similarity between this curve and the release profile of noble gases suggests that HT-peak of noble gases from nanodiamonds is caused by structural transformation of UDD. According to Refs. [84, 85] this transformation proceeds from the surface toward the particle bulk. In this case the temperature of HT-peak should increase with ion penetration depth (the deep layer in the diamond core will be destroyed at higher temperatures). This explanation was confirmed by the mass-spectrometric detection of nitrogen, present in UDD as bulk impurity, released during graphitization of UDD. To our knowledge, this is the first direct observation of nitrogen desorption from UDD. These results indicate that the thermal release of noble gases from nanodiamond grains is associated with atoms trapped inside diamond crystal at sites belonging to two main types. The LT-peak is formed by the atoms escaping the sites of low activation energies. The HT release is caused by the atoms more tightly bounded in

243


Ion implanted Ar

1550

1460

o

o

the crystal lattice. The temperature needed for thermal activation of their escape is higher than the temperature of graphitization of nanodiamonds. The shape of HT-peak is governed by the kinetics of annihilation of the diamond structure.

Ar release

250eV

50 40 30 20

2+

N2(N )

"Graphitization" rate (Butenko et al.)

10

Transformed diamond fraction, %

1530

o

3000eV

N2 release

244

0 800

1000

1200

1400

1600

o

TEMPERATURE, C

Figure 6.13

High-temperature profiles of gas release (N2 and implanted Ar of different energies) and of “diamond-onions transition” (calculated from the data of Refs. [84, 85]).

6.4 Conclusion The presented data demonstrate the advantages of TDMS as analytical method for characterization of nanodiamond surface chemistry. Different types of UDD are characterized by differences in concentration, composition, and structure of the surface functional groups formed during synthesis and purification of UDD. These

References

groups are decomposed with the formation of volatile products in different temperature intervals. The temperature profiles of these volatiles measured by TDMS could be considered as “the chemical identifiers” of UDD both in the as-received forms and after chemical modifications. It was shown that the problem of unification of different UDD, distinguished by the details of synthesis and extraction technologies, can hardly be solved by additional acid purification. Such a treatment does not remove entirely the difference in the initial surface properties of different UDD. Moreover, the use of identical “standard” procedure for the extraction of UDD from the detonation carbon soot of different types does not lead to the necessary level “of the unification” of the UDD surface chemistry. One can suggest that the chemical activity of UDD is controlled by stable “hereditary” features formed on the stage of detonation synthesis. These features are not removed entirely by standard extraction procedure in the UDD production. The modification of UDD surface by soft thermal oxidation in air can be considered as the simple and effective method of the unification of the chemical properties of UDD surface, at least with respect to the oxygen-containing functional groups. The studies of noble gases in UDD by means of TDMS allowed clarifying some questions of cosmochemical relevance. In particular, valuable information was obtained on the processes of trapping of noble gases by nanodiamond grains in interstellar space and on the mechanisms of noble gas release from these grains in the course of the laboratory studies.

Acknowledgment This work was funded in part by the Russian Federal Agency for Science and Innovations, State Contract No. 02.523.12.3024 dated August 06, 2009.

References 1. Lyamkin, A. I., Petrov, E. A., Ershov, A. P., Sakovich, G. V., Staver, A. M., and Titov, V. M. (1988). Production of diamond from explosives, Dokl. Acad. Nauk SSSR, 302, 611–613 (in Russian). 2. Greiner, N. R., Philips, D. S., Johnson, J. D., and Volk, F. (1988). Diamonds in detonation soot, Nature, 333, 440–442.

245

246


3. Dolmatov, V. Y. (2001). Detonation synthesis ultradispersed diamonds: properties and applications, Russ. Chem. Rev., 70, 607–627. 4. Shenderova, O., and Gruen, D. (Eds.). (2006). Ultranano-Crystalline Diamond: Synthesis, Properties, and Applications, William-Andrew Publishing, New York, 2006. 5. Dolmatov, V. Yu. (2009). Composition materials based on elastomer and polymer matrices filled with nanodiamonds of detonation synthesis, Nanotechnol. Russ., 4, 556–575. 6. Zhao, Y. Q., Lau, K. T., and Li, H. L. (2008). Manufacture of a homogenous nano-diamond/poly(lactic acid) bio-engineered composite, Adv. Mat. Res., 47–50, 1221–1224. 7. Maitra, U., Prasad, K. E., Ramamurty, U., and Rao, C. N. R. (2009). Mechanical properties of nanodiamond-reinforced polymer-matrix composites, Solid State Commun., 149, 1693–1697. 8. Purtov, K. V., Puzyr, A. P., and Bondar, V. S. (2008). Nanodiamond sorbents: New carriers for column chromatography of proteins, Doklady Biochem. Biophys., 419, 72–74. 9. Nesterenko, P. N., and Haddad, P. R. (2009). Diamond-related materials as potential new media in separation science, Anal. Bioanal. Chem., 396, 205–211. 10. Bogatyreva, G. P., Marinich, M. A., and Gvyazdovskaya, V. L. (2000). Diamond — an adsorbent of a new type, Diam. Relat. Mater., 9, 2002–2005. 11. Su, D., Maksimova, N. I., Mestl, G., Kuznetsov, V. L., Keller, V., Schlögl, R., and Keller, N. (2007). Oxidative dehydrogenation of ethylbenzene to styrene over ultra-dispersed diamond and onion-like carbon, Carbon, 45, 2145–2151. 12. Mavrodinova, V., Popova, M., Mitev, D., Stavrev, S., Vassilev, S., and Minchev, C. (2007). Study on the preparation and the catalytic performance of Ni-modified shock-wave synthesized diamond blends and nanodispersed diamond, Catalysis Commun., 8, 1502–1506. 13. Mochalin, V. N., and Gogotsi, Yu. (2009). Wet chemistry route to hydrophobic blue fluorescent nanodiamond, J. Am. Chem. Soc., 131, 4594–4595. 14. Huang, H., Pierstorff, E., Osawa, E., and Ho, D. (2007). Active nanodiamond hydrogels for chemotherapeutic delivery, Nano Lett., 7, 3305–3314. 15. Manus, L. M., Mastarone, D. J., Waters, E. A., Zhang, X.-Q., Schultz-Sikma, E. A., MacRenaris, K. W., Ho, D., and Meade, Th. J. (2010). Gd(III)-

References

nanodiamond conjugates for MRI contrast enhancement, Nano Lett., 10, 484–489. 16. Pramatarova, L., Dimitrova, R., Pecheva, E., Spassov, T., and Dimitrova, M. (2007). Peculiarities of hydroxyapatite/nanodiamond composites as novel implants, J. Phys. Conf. Ser., 93, 12049–12055. 17. Holt, K. B. (2007). Diamond at the nanoscale: Applications of diamond nanoparticles from cellular biomarkers to quantum computing, Philos. Transact. A Math. Phys. Eng. Sci., 365, 2845–2861. 18. Krueger, A. (2008). New carbon materials: Biological applications of functionalized nanodiamond materials, Chem. Eur. J., 14, 1382–1390. 19. Schrand, A. M., Hens, S. A. C., and Shenderova, O. A. (2009). Nanodiamond particles: Properties and perspectives for bioapplications, Crit. Rev. Solid State Mater. Sci., 34, 18–74. 20. Savvakin, G. I., and Trefilov, V. N. (1991). The formatuin of structure and properties of ultradispersed diamonds under detonation of various condensed carbon-containing explosives with negative oxygen balance, Dokl. Akad. Nauk SSSR, 321, 99–103 (in Russian). 21. Kolomiichuk, V. I. and Mal’kov, I. Yu. (1993). Study of the synthesis of ultradispersed diamond phase under the conditions of the detonation of mix compositions, Fizika Goreniya i Vzryva, 29, 120–128. 22. Lewis, R. S., Tang, M., Wacker, J. G., Anders, E., and Steel E. (1987). Interstellar diamonds in meteorites, Nature, 326, 160–162. 23. Lewis, R. S., Anders, E., and Draine, B. T. (1989). Properties, detectability and origin of interstellar diamonds in meteorites, Nature, 339, 117–121. 24. Viecelli, J. A., Bastea, S., Glosli, J. N., and Ree, F. H. (2001). Phase transformations of nanometer size carbon particles in shocked hydrocarbons and explosives, J. Chem. Phys., 115, 2730–2736. 25. Kulakova, I. (2004). Surface chemistry of nanodiamonds, Phys. Solid State, 46, 636–643. 26. Koshcheev A. P. (2009). Thermodesorption mass spectrometry in the light of solution of the problem of certification and unification of the surface properties of detonation nano-diamonds, Russ. J. General Chem., 79, 2033–2044. 27. Mitev, D., Dimitrova, R., Spassova, M., Minchev, Ch., and Stavrev, S. (2007). Surface peculiarities of detonation nanodiamonds in dependence of fabrication and purification methods, Diam. Relat. Mater., 16, 776–780. 28. Kuznetsov, V. L., Aleksandrov, M. N., Zagoruiko, I. V., Chuvilin, A. L., Moroz, E. M., Kolomiichuk, V. N., et al. (1991). Study of ultradispersed

247

248


diamond powders obtained using explosion energy, Carbon, 29, 665–668. 29. Mironov, E., Koretz, A., and Petrov, E. (2002). Detonation synthesis ultradispersed diamond structural properties investigation by infrared absorption, Diam. Relat. Mater., 11, 872–876. 30. Jiang, T., and Xu, K. (1995). FTIR study of ultradispersed diamond powder synthesized by explosive detonation, Carbon, 33, 1663–1671. 31. Liu, Y., Gu, Z. N., Margrave, J. L., and Khabashesku, V. N. (2004). Functionalisation of nanoscale diamond powder: fluoro-, alkyl-, amino-, and amino acid-nanodiamond derivatives, Chem. Mater., 16, 3924–3930. 32. Ray, M. A., Shenderova, O., Hook, W., Martin, A., Grishko, V., Tyler, T., Cunningham, G. B., and McGuire, G. (2006). Cold plasma functionalization of nanodiamond particles, Diam. Relat. Mater., 15, 1809–1812. 33. Spitsyn, B. V., Davidson, J. L., Gradoboev, M. N., Galushko, T. B., Serebryakova, N. V., Karpukhina, T. A., Kulakova, I. I., and Melnik, N. N. (2006). Inroad to modification of detonation nanodiamond, Diam. Relat. Mater., 15, 296–299. 34. Lisichkin, G. V., Korol’kov, V. V., Tarasevich, B. N., Kulakova, I. I., and Karpukhin, A. V. (2006). Photochemical chlorination of nanodiamond and interaction of its modified surface with C-nucleophiles Izvestiya Akademii Nauk. Seriya Khimicheskaya, 12, 2130–2137 (in Russian). 35. Kulakova, I. I. (2004). Modification of detonation nanodiamonds: the effect on physicochemical properties. Ross. Khim. Zh. (Zh. Ros. Khim. Ob–va im., D.I. Mendeleeva), 48, 97–106. 36. Yeganeh, M., Coxon, P. R., Brieva, A. C., Dhanak, V. R., Siller, L., and Butenko, Yu. V. (2007). Atomic hydrogen treatment of nanodiamond powder studied with photoemission spectroscopy, Phys. Rev. B, 75, 155404–155411. 37. Krueger, A., Stegk, J., Liang, Y., Lu, L., and Jarre, G. (2008). Biotinylated nanodiamond: Simple and efficient functionalization of detonation diamond, Langmuir, 24, 4200–4204. 38. Krueger, A. (2008). The structure and reactivity of nanoscale diamond, J. Mater. Chem., 18, 1485–1492. 39. Cunningham, G., Panich, A. M., Shames, A. I., Petrov, I., and Shenderova, O. (2008). Ozone-modified detonation nanodiamonds, Diam. Relat. Mater., 17, 650–654. 40. Petrov, I., Shenderova, O., Grishko, V., Grichko, V., Tyler, T., Cunningham, G., and McGuire G. (2007). Detonation nanodiamonds simultaneously

References

purified and modified by gas treatment, Diam. Relat. Mater., 16, 2098–2103. 41. Portet, C., Kazachkin, D., Osswald, S., Gogotsi, Y., and Borguet, E. (2010). Impact of synthesis conditions on surface chemistry and structure of carbide-derived carbons, Thermochimica Acta, 497, 137–142. 42. Figueiredo, J. L., Pereira, M. F. R., Freitas, M. M. A., and Orfao, J. J. M. (1999). Modification of the surface chemistry of activated carbons, Carbon, 37, 1379–1389. 43. Bobrov, K., Shechter, H., Hoffman, A., and Folman, M. (2002). Molecular oxygen adsorption and desorption from single crystal diamond (111) and (110) surfaces, Appl. Surf. Sci., 196, 173–180. 44. Matsumoto, S., Kanda, H., Sato, Y., and Setaka, N. (1977). Thermal desorption spectra of the oxidized surfaces of diamond powders, Carbon, 15, 299–302. 45. Matsumoto, S., and Setaka, N. (1979). Thermal desorption spectra of hydrogenated and water treated diamond powders, Carbon, 17, 485–489. 46. Ando, T., Yamamoto, K., Ishii, M., Kamo, M., and Sato, Y. (1993). Vapour-phase oxidation of diamond surfaces in O2 studied by diff use reflectance Fourier-transform infrared and temperature-programmed desorption spectroscopy, J. Chem. Soc. Faraday Trans., 89, 3635–3640. 47. Ando, T., Ishii, M., Kamo, M., and Sato, Y. (1993). Thermal hydrogenation of diamond surfaces studied by diffuse reflectance Fourier-transform infrared, temperature-programmed desorption and laser Raman spectroscopy, J. Chem. Soc. Faraday. Trans., 89, 1783–1789. 48. Ando, T., Rawles, R. E., Yamamoto, K., Kamo, M., Sato, Y., and NishitaniGamo, M. (1996). Chemical modification of diamond surfaces using a chlorinated surface as an intermediate state, Diam. Relat. Mater., 5, 1136–1142. 49. Tapraeva, F. M., Pushkin, A. N., Kulakova, I. I., Rudenko, A. P., and Kruk, V. B. (1989). Thermal desorption study of the chemical modification of a diamond surface. Russ. J. Phys. Chem., 63, 1463–1466. 50. Semchinova, O., Uffmann, D., Neff, H., and Smirnov, E. P. (1996). Growth, preparation and surface modification of microcrystalline diamond powder for the synthesis of diamond ceramics. J. Europ. Ceram. Soc., 16, 753–758. 51. Su, C., and Lin, J.-C. (1998). Thermal desorption of hydrogen from the diamond C(100) surface, Surf. Sci., 406, 149–166. 52. Hadenfeldt, S. and Benndorf, C. (1998). Adsorption of fluorine and chlorine on the diamond (100) surface, Surf. Sci., 402–404, 227–231.

249

250


53. Yamada, T., and Chuang, T. (2003). Thermal desorption and laser induced desorption of NO from adlayers of NO on diamond C(111), Appl. Surf. Sci., 211, 31–47. 54. Ikeda, Y., Saito, T., Kusakabe, K., Morooka, Sh., Maeda, H., Taniguchi, Y., and Fujiwara, Y. (1998). Halogenation and butylation of diamond surfaces by reactions in organic solvents, Diam. Relat. Mater., 7, 830–834. 55. Jiang, T., and Xu, K., Ji, S. (1996). FTIR studies on the spectral changes of the surface functional groups of ultradispersed diamond powder synthesized by explosive detonation after treatment in hydrogen, nitrogen, methane and air at different temperatures, J. Chem. Soc. Faraday Trans., 92, 3401–3406. 56. Ji, S., Jiang, T., Xu, K., and Li, S. (1998). FTIR study of the adsorption of water on ultradispersed diamond powder surface, Appl. Surf. Sci., 133, 231–238. 57. Bogatyreva, G. P., Marinich, M. A., Bazalii, G. A., Oleinik, N. A., Ishchenko, E. V., and Gvyazdovskaya, V. L. (2004). The formation of energetic state and adsorption ability of the surface of nanodiamond powders during their production. Fizika Tv. Tela, 46, 649–651 (in Russian). 58. Koscheev, A. P., Panin, I. A., and Ott, U. (1998). Thermal modification of synthetic nanodiamonds as analog of meteoritic diamond grains, Meteor. Planet. Sci., 33, A88. 59. Butenko, Yu. V., Kuznetsov, V. L., Paukshtis, E. A., Stadnichenko, A. I., Mazov, I. N., Moseenkov, S. I., Boronin, A. I., and Kosheev, S. V. (2006). The thermal stability of nanodiamond surface groups and onset of nanodiamond graphitization, Fullerenes Nanotubes Carbon Nanostruct., 14, 557–564. 60. Koscheev, A. P., Serzhantov, A. E., Merchel, S., Ott, U., Guillois, O., and Reynaud, C. (2003). Surface chemistry of chemically treated diamond nanograins, Lunar and Planetary Science, XXXIV, Abstract #1287, Lunar and Planetary Institute, Houston (CD-ROM). 61. Koscheev, A. P., Zaripov, N. V., and Ott, U. (2005). Diamond nanograins in carbon soot: Does the chemistry of extracted diamonds depend on the properties of pristine soot? Lunar and Planetary Science, XXXVI, Abstract #1406, Lunar and Planetary Institute, Houston (CD-ROM). 62. Koshcheev, A. P., Gorokhov, P. V., Gromov, M. D., Perov, A. A., and Ott, U. (2008). The chemistry of the surface of modified detonation nanodiamonds of different types, Russ. J. Physical Chem. A, 82, 1708–1714. 63. Koscheev, A. P., and Ott, U. (2000). Mechanism of noble gas release during pyrolysis of nanodiamond grains, Meteor. Planet. Sci., 35, A92.

References

64. Gorokhov, P. V., Zaripov, N. V., and Koscheev, A. P. (2006). Surface chemistry modification of nanodiamonds during electrophoresis in aqueous solutions, Abstr. of joint Int. Conf. “Nanocarbon & Nanodiamond 2006,” St. Petersburg, p. 84. 65. Koscheev, A. P., Gorokhov, P. V., Gromov, M. D., and Daulton, T. L. (2008). Nitrogen release during high temperature annealing of detonation nanodiamonds in vacuum, Abstr. of joint Int. Conf. “Nanocarbon & Nanodiamond 2008,” St. Petersburg, p. 50. 66. Gibson, N., Shenderova, O., Luo, T. J. M., Moseenkov, S., Bondar, V., Puzyr, A., Purtov, K., Fitzgerald, Z., and Brenner, D. W. (2009). Colloidal stability of modified nanodiamond particles. Diam. Relat. Mater., 18, 620–626. 67. Aleksenskii, A. E., Baidakova, M. V., Vul’, A. Ya., Davydov, V. Yu., and Pevtsova, Yu. A. (1997). Phase transition diamond-graphite in ultradispersed diamond clusters, Fizika Tv. Tela, 39, 1125–1134 (in Russian). 68. Yoshikava, M., Mori, Y., Obata, H., Maegava, M., Katagiri, G., Ishida, H., and Ishitani, A. (1995). Raman scattering from nanometer-sized diamond, Appl. Phys. Lett., 67, 694–696. 69. Mochalin, V., Osswald, S., and Gogotsi, Yu. (2009). Contribution of functional groups to the Raman spectrum of nanodiamond powders, Chem. Mater., 21, 273–279. 70. Sappok, R., and Boehm, H. P. (1968). Chemie der oberfläche des diamanten–I benetzungäswrmen, elektronenspinresonanz und infrarotspektren der oberflächenhydride, -halogenide und-oxide, Carbon, 6, 283–293. 71. Chiganova, G. A. (2000). Aggregation of particles in ultradispersed diamond hydrosols. Colloid. J., 62, 238–243. 72. Merchel, S., Ott, U., Herrmann, S., Spettel, B., Faestermann, T., Knie, K., Korschinek, G., Rugel, G., and Wallner, A. (2003). Presolar nanodiamonds: Faster cleaner, and limits on platinum-HL, Geochim. Cosmochim. Acta, 67, 4949–4960. 73. Cheng, C.-L., Chang, H.-C., Lin, J.-C., Song, K.-J., and Wang, J.-K. (1997). Direct observation of hydrogen etching anisotropy on diamond single crystal surfaces, Phys. Rev. Lett., 78, 3713–3716. 74. de Theije, F. K., Roy, O., van der Laag, N. J., and van Enckevort, W. J. P. (2000). Oxidative etching of diamond, Diam. Relat. Mater., 9, 929–934. 75. Chen, P., Huang, F., and Yun, Sh. (2003). Characterization of the condensed carbon in detonation soot. Carbon, 41, 2093–2099.

251

252


76. Iakoubovskii, K., Baidakova, M. V., Wouters, B. H., Stesmans, A., Adriaenssens, G. J., Vul’, A. Ya., and Grobet, P. J. (2000). Structure and defects of detonation synthesis nanodiamond. Diam. Relat. Mater., 9, 861–865. 77. Osswald, S., Yushin, G., Mochalin, V., Kucheyev, S. O., and Gogotsi, Yu. (2006). Control of sp2/sp3 carbon ratio and surface chemistry of nanodiamond powders by selective oxidation in air, J. Am. Chem. Soc., 128, 11635–11642. 78. Huss, G. R., and Lewis, R. S. (1994). Noble gases in presolar diamonds I: Three distinct components and their implications for diamond origins. Meteoritics, 29, 791–810. 79. Koscheev, A. P., Gromov, M. D., Mohapatra, R. K., and Ott, U. (2001). History of trace gases in presolar diamonds inferred from ionimplantation experiments, Nature, 412, 615–617. 80. Koscheev, A. P., Gromov, M. D., Herrmann, S., and Ott, U. (1998). Mass fractionation and thermal release from nanodiamonds of low-energy implanted xenon, Meteorit. Planet. Sci., 33, A87–A88. 81. Koscheev, A. P., Gromov, M. D., Zaripov, N. V., and Ott, U. (2004). Release of noble gases during pyrolysis of meteoritic and synthetic diamonds: A new approach, Meteorit. Planet. Sci., 39, A55. 82. Koscheev, A. P., Gromov, M. D., Gorokhov, P. V., Ott, U., Huss, G. R., and Daulton, T. L. (2005). Ion implantation into nanodiamonds and the mechanism of high temperature release of noble gases from meteoritic diamonds, Meteorit. Planet. Sci., 40, A87. 83. Huss, G. R., Ott, U., and Koscheev, A. P. (2008). Noble gases in presolar diamonds III: Implications of ion implantation experiments with synthetic nanodiamonds, Meteorit. Planet. Sci., 43, 1811–1826. 84. Kuznetsov, V. L., Butenko, Yu. V., Chuvilin, A. L., et al. (2001). Electrical resistivity of graphitized ultradispersed diamond and onion-like carbon, Chem. Phys. Lett., 336, 397–404. 85. Butenko, Yu. V., Kuznetsov, V. L., Chuvilin, A. L., Kolomiichuk, V. N., et al. (2000). Kinetics of the graphitization of dispersed diamonds at ‘‘low’’ temperatures, J. Appl. Phys., 88, 4380–4388.