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WO2001077016A1 - Procede de production de particules de diamant pures a partir d'un autre allotrope du carbone, particules de diamant pouvant etre obtenues par ce procede et ses applications - Google Patents

Procede de production de particules de diamant pures a partir d'un autre allotrope du carbone, particules de diamant pouvant etre obtenues par ce procede et ses applications Download PDF

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Publication number
WO2001077016A1
WO2001077016A1 PCT/BE2000/000052 BE0000052W WO0177016A1 WO 2001077016 A1 WO2001077016 A1 WO 2001077016A1 BE 0000052 W BE0000052 W BE 0000052W WO 0177016 A1 WO0177016 A1 WO 0177016A1
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Prior art keywords
diamond particles
making
particles according
diamond
graphite
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English (en)
Inventor
Jean-Christophe Charlier
Jean-Paul Issi
Andrei Palenichenko
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Universite Catholique de Louvain UCL
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Universite Catholique de Louvain UCL
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Priority to AU45291/00A priority Critical patent/AU4529100A/en
Publication of WO2001077016A1 publication Critical patent/WO2001077016A1/fr
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/25—Diamond
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/25—Diamond
    • C01B32/26—Preparation

Definitions

  • the present invention relates to a process for making discrete diamond particles from another allotropic form of carbon, and more particularly to an economically and technically efficient process for making discrete diamond particles of significant and variable size from graphite.
  • the present invention additionally relates to a process for making high purity discrete diamond particles of potentially any size with a crystalline perfection close to or even better than that of diamonds from natural origin.
  • the present invention further relates to discrete diamond particles obtainable from such a process, having specific characteristics and being useful for virtually any industrial or ornamental application of conventional diamond, namely for jewellery or for making cutting or grinding tools such as drill bits of oil drills, or for making polishing slurries or magnetic tape coatings or for the electronic, particularly the semiconductor, industry.
  • Carbon is known for a long time to exist under two crystalline forms, graphite and diamond.
  • Graphite consisting of an undetermined number of sp2 hybridized carbon atoms arranged in parallel planes called graphenes, is widely spread over earth but is often mixed with other minerals, thus preventing its ready industrial exploitation.
  • a few mines are able to produce high purity graphite, namely in Korea, Mexico and other countries.
  • Graphite may also be produced artificially.
  • Diamond is the second, metastable, crystalline form of carbon. Its domain of stability ranges among high pressures, thus making studies on the thermodynamic equilibrium of carbon rather difficult. Diamond is the hardest natural known substance, it crystallizes in the cubic system and is covalently bound by single bonds in a tetrahedral structure of sp3 bonded carbon atoms. It also has the highest thermal conductivity of any known substance, which is about five times that of copper. For this reason, diamonds used in cutting and grinding tools do not become hot, thus greatly contributing to their usefulness and desirability in such applications.
  • Such methods include for instance static crystallization from molten metals or alloys at pressures above 50,000 bars and temperatures above 1500°K, shock conversion from graphite at pressures of about 300,000 bars and temperatures of about 1300°K, or static conversion from graphite at pressures above 130,000 bars and temperatures of about 3300°K.
  • shock conversion from graphite at pressures of about 300,000 bars and temperatures of about 1300°K or static conversion from graphite at pressures above 130,000 bars and temperatures of about 3300°K.
  • 5,366,556 discloses a physical deposition process for producing a diamond-like film by physical ablation of a carbon source, such as a high purity carbon rod, in the vicinity of a metallic, glass or other substrate by means of an ion beam, arc or laser, thereby initiating bonding of the atoms of a carbon film in all possible forms, including the sp3 form (i.e. diamond).
  • a carbon source such as a high purity carbon rod
  • 5,300,203 provides a process for making fullerenes by vaporizing carbon from a carbon source with a laser beam to produce a carbon vapour that is carried away from the carbon vaporization zone by an inert gas stream, and passing the inert gas stream and carbon vapour through a fullerene growth and formation zone where the temperature is between 1 ,000°C and 2,000°C and the residence time of the carbon vapour ranges from 0.1 millisecond to 100 seconds.
  • 5,370,855 discloses forming synthetic hydrogen defect free diamond on a substrate by providing a vapour of fullerenes in an inert gas, exposing said vapour to energy-imparting means, ionizing said fullerenes having received energy and impinging said ionized fullerenes on said substrate until a thick diamond or diamond-like film is obtained.
  • This method thus does not yield individual diamond particles but, alike the chemical vapour deposition method, a continuous film of crystalline diamond.
  • U.S. Patent No. 5,449,491 also discloses producing diamond crystals by hyperquenching a metal-carbon matrix containing iron and iron fullerites that has been heated to about its critical temperature at a rate sufficiently rapid to collapse fullerene structures present in the matrix into diamond crystals. This method thus produces a metallic solid comprising a metal-carbon matrix, fullerenes and diamond crystals from which the said crystals must still be extracted.
  • the present invention is based, at least in part, on the unexpected discovery that discrete diamond particles can be made from a solid material containing an allotropic form of carbon other than diamond by subjecting said solid material to Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas in a vessel maintained at a pressure not above about 3,000 bars and containing an inert or reducing gas.
  • the present invention is based on the unexpected discovery that high purity discrete diamond particles can be made by subjecting high purity graphite to Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas in a vessel maintained at a pressure less than or equal to atmospheric pressure and containing an inert (such as noble gas) or reducing (such as hydrogen) gas.
  • an inert such as noble gas
  • reducing such as hydrogen
  • the present invention also provides for discrete diamond particles obtainable from the said process and having a size in the range of about 1 ⁇ m to about 100 ⁇ m, the said discrete diamond particles being useful namely as cutting or grinding tools such as drill bits of oil drills or in the production of polishing slurries or magnetic tape coatings. Additionally, the present invention provides means for obtaining discrete diamond particles of a significantly higher size, e.g. having a size in a range above about 150 ⁇ m, which will make it possible to broaden the range of uses of such diamond particles, namely for jewellery as well as in the field of the electronic, particularly the semiconductor, industry where they may be used as heat sinks.
  • doped diamond particles according to the present invention may be used as high temperature semiconductors as well as small field-emission devices useful for flat panel displays.
  • Diamond particles of the invention can also be used in the field of micro- and nanotechnology, e.g. as micromotor components.
  • the present invention provides means for controlling and maintaining a high initial growth rate of discrete diamond particles, thus participating in the economic efficiency of the process.
  • Figure 1 shows scanning electron micrographs of discrete diamond particles produced according to the invention.
  • Figure 2 shows X-ray scattering data of discrete diamond particles produced according to the invention.
  • FIG. 3 shows a Fourier-transform infrared spectrum of discrete diamond particles produced according to the invention.
  • Figure 4 shows Raman spectra of discrete diamond particles produced according to the invention.
  • a first embodiment of the present invention consists of a process for making discrete diamond particles from a solid material containing an allotropic form of carbon other than diamond by subjecting said solid material to Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas in a vessel maintained at a pressure, i.e.
  • discrete diamond particles according to this embodiment, it is meant a set of individual particles or crystals of the cubic diamond allotropic form of carbon as ordinarily defined, not a continuous thin or thick diamond-like carbon film as obtained in the chemical or physical vapour deposition methods of the prior art. Although in this embodiment individual crystals are obtained and may be readily observed by microscopy as further described, they may also however be arranged or assembled into macroscopic entities such as clusters.
  • the source of carbon used for carrying out the process of the invention may be any known allotropic form of carbon other than diamond. More specifically the source of carbon should be readily available and inexpensive and for this reason it is generally preferred to use graphite or a graphite-containing material as such a source of carbon.
  • the carbon-containing solid material used for performing the first embodiment of the process of the invention preferably comprises the allotropic form of carbon other than diamond, especially the graphite or a graphite-containing material, as its main component since adjuvants and /or additives may interfere with the process of transforming the said allotropic form of carbon into discrete diamond particles.
  • the carbon-containing solid material may also include a binder for such allotropic form, namely any binder already known for binding graphite in usual amounts.
  • the said solid material may take the form of graphite electrodes.
  • An essential feature of the present invention consists of subjecting the carbon-containing solid material to Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas.
  • Joule effect sublimation conditions means conditions sufficient to bring the temperature of the carbon-containing solid material above the sublimation or vaporization temperature of the allotropic form of carbon other than diamond.
  • Providing plasma-forming conditions and/or conditions producing an at least partially ionized gas according to the present invention can be achieved by any conventional technique known in the art for producing plasmas and/or for at least partially ionizing a gas.
  • the term " plasma " as used herein refers to a partially or nearly totally ionized gas which may be further characterized by its electronic density.
  • it is more often sufficient to provide conditions for creating partially ionized gases also usually named " cold plasmas ", the latter being out of thermodynamic equilibrium and being believed to be at temperatures ranging from about 10,000°K to about 100,000°K.
  • Joule effect sublimation conditions and/or plasma-forming conditions may result from providing an effective electrical pulse discharge between at least two electrodes made from a solid material containing an allotropic form of carbon other than diamond, e.g. between a negatively charged graphite or graphite-containing cathode and a positively charged graphite or graphite-containing anode.
  • effective electrical pulse discharge it is meant that the various characteristics of the said discharge, in particular its intensity and duration, as well as the difference of potential between the electrodes should be suitably selected in order to achieve the desired Joule effect sublimation conditions and/or plasma- forming conditions and/or the conditions producing an at least partially ionized gas.
  • the intensity of the electrical pulse discharge is critical to the success of the process, i.e. the said intensity should be sufficient to instantaneously create the plasma-forming conditions and/or the conditions producing an at least partially ionized gas and/or the Joule effect sublimation conditions. Practically, this has been found to mean an electric pulse discharge having a peak current of at least about 550 amps, preferably at least about 600 amps and more preferably at least about 800 amps.
  • the graphite-containing electrodes in order to achieve discrete diamond particles with a particle size in a range above about 150 ⁇ m and/or to achieve an initial growth rate of diamond particles above about 800 ⁇ m/s, it is desirable to subject the graphite-containing electrodes to an electric pulse discharge having a peak current of at least about 1 ,500 amps, possibly up to about 100,000 amps, and preferably a peak current intensity between about 2,000 and 10,000 amps. Peak current intensities up to about 10,000 amps are easily obtained by making use of capacitors conventional in the art and commercially available. Peak current intensities above 10,000 amps and up to 100,000 amps can be obtained by means of a Van der Graaf apparatus.
  • a plasma or an at least partially ionized gas may be observed for instance within the first millisecond, preferably within less than 0.1 millisecond, and more preferably within less than 0.01 millisecond after creating the electrical pulse discharge between the two electrodes. Since the electric current pulse typically decays exponentially versus time, for instance during the discharge of a capacitor, a starting electric current intensity of 1 ,000 amps will be reduced by about one half within a period of time of about 20 milliseconds. As indicated above, the duration of the electric pulse discharge may also be a critical factor for the efficiency of the process according to the present invention.
  • an effective electric pulse discharge i.e. having a minimum current intensity as stated hereinabove
  • a period of time not less than about 0.05 second, preferably not less than 0.1 second, more preferably not less than 0.2 second, depending on the initial peak current intensity that was selected.
  • the difference of potential applied between the electrodes may also be a critical factor for the efficiency of the process according to the present invention.
  • this difference of potential may about 30 volts.
  • the said difference of potential between the electrodes may be kept substantially constant during the electric pulse discharge, for instance by providing means for finely regulating the said difference of potential during the performance of the process according to the present invention.
  • the position of the carbon-containing (e.g. graphite) electrodes in the vessel during the performance of the process may be adjusted as a function of, i.e. taking into account, carbon material (e.g. graphite) consumption.
  • a means may be provided for directly or indirectly estimating the said carbon material consumption, for instance through a measurement of the initial growth rate of discrete diamond particles.
  • subjecting the carbon-containing solid material to Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas can also be achieved by means of applying an effective laser pulse to the said solid material containing an allotropic form of carbon other than diamond.
  • Suitable laser pulse equipment for this purpose is well known to those skilled in the art and can readily be selected and designed as a function of the kind of allotropic form of carbon, especially the kind of graphite or graphite-containing material, to be processed.
  • suitable laser pulse equipment include these selected from the doped insulating laser type, the gas (e.g.
  • the various characteristics of the said pulse in particular its intensity and operating wavelength, as well as the duration of its application, should be suitably selected in order to achieve the desired Joule effect sublimation conditions and/or plasma-forming conditions and/or the conditions producing an at least partially ionized gas.
  • the intensity and the operating wavelength of the laser pulse should be selected in order to achieve a laser pulse power of at least 5.10 5 W/cm 2 , preferably from about 10 6 W/cm 2 to about 5.10 6 W/cm 2 .
  • the intensity of the laser pulse should preferably kept substantially constant during its application to the solid carbon material.
  • the efficiency of the process according to the present invention may be improved by effecting the said process in the presence of an effective amount of at least one suitable catalyst.
  • a suitable catalyst may be cited a metal selected from transition metals and group VIII metals or a compound containing such a metal, for instance nickel, cobalt, yttrium or lanthane.
  • An effective amount of a suitable catalyst can readily be determined by those skilled in the art by reference to the use of such catalysts in alternative processes for making diamond particles such as the above-mentioned high pressure high temperature process.
  • a specific embodiment of such a process making use of a metal-containing catalyst includes sputtering the said metal or metal-containing compound onto the solid material containing an allotropic form of carbon other than diamond.
  • the said metal or metal-containing compound is present in an opened container in the vessel and the said opened container is heated to a temperature sufficient to vaporise the said metal or metal-containing compound.
  • doped discrete diamond particles can be obtained either by doping at least one of the graphite- containing electrodes (in the electric pulse discharge embodiment of the invention) or by directly injecting a dopant-containing gas into the vessel containing the allotropic form of carbon other than diamond.
  • dopant-containing gas as used herein means introducing very small amounts of atoms such as nitrogen and/or boron in order to drastically modify the electronic properties of the host (carbon) material.
  • Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas i.e.
  • the efficiency of the process according to the present invention may be improved, namely in terms of achieving discrete diamond particles with a particle size in a range above about 150 ⁇ m and/or achieving an initial growth rate of diamond particles above about 800 ⁇ m/s, if the solid material containing an allotropic form of carbon other than diamond is soaked in diamond powder particles prior to being subjected to Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas.
  • the said solid material be fed with an energy density of at least 10 6 W/cm 2 , and more preferably at least 5.10 6 W/cm 2 .
  • the energy density or, in the case of an electric pulse discharge, the intensity thereof should be sufficient to generate nucleation and growth of discrete diamond particles in a dense carbon vapour or plasma.
  • the process according to the present invention is carried out in a vessel maintained at a pressure not above about 3,000 bars.
  • pressures under the atmospheric pressure in particular pressures no less than about 0.01 Torr, can be used as well with success especially when it is desired to remove gaseous impurities before subjecting the carbon-containing solid material to Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas.
  • the vessel itself must be constructed to support the pressure maintained therein and also must be made from a material which is inert with respect to carbon and to the plasma or partially ionized gas resulting therefrom.
  • a material suitable for this purpose consists of stainless steel.
  • the vessel may be a stainless steel vacuum-tight chamber which, in order gaseous impurities before an electric or laser pulse generation, is filled with an inert gas such as helium or argon, which is then pumped out by any suitable means.
  • the process according to the present invention is carried out in a vessel containing an inert or reducing gas.
  • containing a gas it is meant that it is unnecessary, for the efficiency of the process, to provide a high vacuum in the said vessel and therefore some gas will always remain therein.
  • inert gas it is meant a noble gas such as helium, neon, argon, krypton, xenon or a mixture thereof.
  • reducing gas it is meant hydrogen or a hydrogen-generating gaseous compound.
  • the process is carried out in the absence of an oxidizing atmosphere which would permit transformation of the carbon-containing solid material into carbon monoxide instead of diamond particles.
  • the vessel in which the carbon-containing solid material is subjected to Joule effect sublimation conditions and/or plasma- forming conditions and/or to conditions producing an at least partially ionized gas preferably further comprises at least one substrate for depositing the diamond particles formed.
  • the said substrate may be made from any material which is non-reactive with carbon under the applied conditions. It may be selected, for instance, from nickel, silicon, aluminium, copper, quartz or any other such solid material.
  • the said substrate is advantageously maintained at room temperature during the electric pulse discharge or laser pulse or other means for subjecting the carbon-containing solid material to Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas.
  • the carbon-containing solid material in particular the graphite electrodes
  • the carbon-containing solid material are heat-treated before and/or during the electric pulse discharge, for instance by means of a thermocouple, in order to clean the said material and eliminate any species possibly adsorbed on its surface.
  • the graphite electrodes may be submitted to a continuous heat treatment at a temperature of about 300°C to about 600°C before and until the electric pulse discharge.
  • the carbon-containing solid material is in the form of graphite electrodes, that the said two electrodes are maintained in contact together at least during the initial period of the process.
  • Another embodiment of the present invention consists of a process for making high purity discrete diamond particles from high purity graphite by subjecting high purity graphite electrodes to Joule effect sublimation conditions and/or plasma-forming conditions and/or to conditions producing an at least partially ionized gas in a vessel maintained at a pressure not above about 3,000 bars and containing an inert or reducing gas.
  • discrete diamond particles plasma particles, “Joule effect sublimation conditions” and “ plasma- forming conditions " as used herein should be understood along with their definitions hereinabove.
  • high purity means a purity compatible with the necessary electrical conductivity, for instance at least 99.9%, preferably at least 99.99 % and more preferably at least 99.995 %, the substitutional impurities generally consisting of nitrogen and/or boron.
  • Yet another embodiment of the present invention consists of discrete diamond particles obtainable from the various embodiments of the process such as above described and having a size in the range of about 1 ⁇ m to about 20 mm.
  • the various specific embodiments of the process of this invention make it possible to obtain either rather small discrete diamond particles, for instance having a size in the range of about 1 ⁇ m to about 100 ⁇ m or else larger discrete diamond particles having a size in a range above about 150 ⁇ m.
  • the size of such discrete diamond particles and their density on the substrate surface on which they deposit were found to be independent of the nature of the substrate, at least when said substrate is selected from nickel, silicon, aluminium, copper and quartz.
  • the size of discrete diamond particles does not either depend on the distance between the substrate and the graphite electrodes, at least as far as the said distance ranges from about 5 to about 100 mm.
  • hundreds of brilliant colourless particles are detectable on the substrate by an optical polarization microscope.
  • These discrete particles do not stick to the substrate and can therefore be easily removed from said substrate by gently shaking in a hydrocarbon solvent such as hexane, then followed by vaporization of the said solvent.
  • the diamond particles of the present invention can easily be used namely as cutting or grinding tools such as drill bits of oil drills, or for making polishing slurries or magnetic tape coatings. They can also be used for or included into a diamond synthesis process.
  • discrete diamond particles are obtainable from another allotropic form of carbon, in particular from high purity graphite, without externally applied pressures,
  • Example 1 production of discrete diamond particles from graphite
  • a stainless steel vessel is provided with two high purity (99.999%) graphite electrodes initially maintained in contact together and with a 10 cm 2 plate substrate made of quartz which is located at a distance of 5 mm from the said graphite electrodes.
  • the vessel is filled with helium, which is then pumped out.
  • Dynamic pumping down to 0.02 Torr is carried out through low temperature (77°K) adsorption and standard room-temperature filters connected in series. This procedure is repeated several times, while a continuous heat treatment of the graphite electrodes at 700°K is maintained by means of an electrical current.
  • the graphite electrodes are connected to a power supply comprising an electric capacitor (0.5 F) initially charged to 30 V.
  • An electrical pulse discharge with an initial intensity of 1 ,000 A is provided, by means of the power supply, between the two sharpened tips (0.5 mm in diameter) of the graphite electrodes, thus resulting in the formation of a carbon plasma which can be observed through a transparent opening on the top of the vessel, if desired.
  • the electric current pulse decays exponentially with time and thus is only about 500 A after 20 milliseconds.
  • the duration of the pulse varies within 20 to 100 milliseconds.
  • the quartz substrate is maintained at room temperature, within 10°K, by thermally anchoring it to a heat sink, a 500 g copper block at room temperature.
  • the temperature of the quartz substrate is constantly monitored by a chromel-alumel thermocouple (1°K accuracy), with its junction anchored to a region of the substrate just below the graphite electrode tips area.
  • the energy density fed to the graphite electrode tips is calculated to be about 10 7 W/cm 2 .
  • the 10 cm 2 plate substrate made of quartz is replaced with a 10 cm 2 plate substrate made of nickel, silicon, aluminium or copper. This does not result in a substantial change in the appearance, size, distribution and amount of the discrete diamond particles collected on the said plate.
  • the quartz substrate is located at a distance of 100 mm (instead of 5 mm) from the graphite electrodes. This does not result in a significant change in the appearance, size, distribution and amount of the discrete diamond particles collected on the said substrate.
  • the discrete diamond particles produced according to example 1 were characterized by different methods as follows.
  • Figure 1a shows a locally high concentration of diamond microparticles on an aluminium substrate.
  • Figure 1b showing the enlarged area of rectangle in figure 1a indicates an average size of these diamond microcrystallites of about 10 ⁇ m.
  • the absorption bands at 1 ,800-2,500 cm -1 are the well known signature of multi-phonon absorption processes in diamond crystals.
  • the absorption bands at 1 ,100 cm -1 and 1 ,290 cm -1 are attributed to structural defects in the diamond microcrystals, such as small mixed sp 2 - sp 3 regions. Nevertheless, the concentration of such structural defects or possible contamination with substitutional nitrogen must be small, otherwise the single- phonon mode (below 1 ,400 cm -1 ) would have been infrared-active. This is clearly not the case here. No absorption bands associated with C-H vibrations (650-1 ,650 cm -1 bending and 2,700-3,310 c ⁇ r 1 stretching) were detected in the infrared spectrum.
  • microparticles are assumed to be type lb or lla diamond, according to the classification of J.E. Field in Diamond (ed. Clausing) 17-35 (Plenum, New-York, 1991 ).
  • Figure 4a exhibits a sharp first-order peak at 1 ,331 cm -1 which is the characteristic signature of the Raman-active phonon at the r point of the Brillouin zone for cubic diamond structures, as stated by Yarbrough et al. in Science 247, 688-696 (1990). Both the full-width at half-maximum value of the dominant peak (3.5 cm -1 width) and the diamond-peak-to-background ratio (of about 200/1 ) confirm the crystalline perfection of these diamond microparticles.
  • Figure 4b is an enlarged background spectrum illustrating a 2,100-2,700 cm -1 peak, in the region where scattering by optical phonons is dominant, which is the signature of the second- order Raman-active phonon of cubic diamond.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
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  • Inorganic Chemistry (AREA)
  • Carbon And Carbon Compounds (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

L'invention concerne un procédé de production de particules de diamant pures à partir d'un matériau solide contenant une forme allotrope de carbone autre que le diamant, consistant à soumettre ledit matériau solide à des conditions de sublimation à effet Joule et/ou des conditions de formation de plasma et/ou des conditions produisant un gaz ionisé au moins partiellement dans une cuve maintenue à une pression ne dépassant pas 3000 bars et contenant un gaz inerte ou de réduction.
PCT/BE2000/000052 2000-04-10 2000-05-10 Procede de production de particules de diamant pures a partir d'un autre allotrope du carbone, particules de diamant pouvant etre obtenues par ce procede et ses applications Ceased WO2001077016A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU45291/00A AU4529100A (en) 2000-04-10 2000-05-10 Process for making pure diamond particles from another carbon allotrope, diamondparticles obtainable by such process and applications thereof

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US54598400A 2000-04-10 2000-04-10
US09/545,984 2000-04-10

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112357918A (zh) * 2020-11-03 2021-02-12 中国林业科学研究院林产化学工业研究所 以植物纤维为原料制备的纳米金刚石及其方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4303567A1 (de) * 1993-02-08 1994-08-11 Friedrich Dr Ing Stricker Herstellung synthetischer Diamanten
US5437243A (en) * 1992-07-01 1995-08-01 Pike-Biegunski; Maciej J. Process for fabricating diamond by supercritical electrical current
US5900225A (en) * 1994-08-09 1999-05-04 Qqc, Inc. Formation of diamond materials by rapid-heating and rapid-quenching of carbon-containing materials

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5437243A (en) * 1992-07-01 1995-08-01 Pike-Biegunski; Maciej J. Process for fabricating diamond by supercritical electrical current
DE4303567A1 (de) * 1993-02-08 1994-08-11 Friedrich Dr Ing Stricker Herstellung synthetischer Diamanten
US5900225A (en) * 1994-08-09 1999-05-04 Qqc, Inc. Formation of diamond materials by rapid-heating and rapid-quenching of carbon-containing materials

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112357918A (zh) * 2020-11-03 2021-02-12 中国林业科学研究院林产化学工业研究所 以植物纤维为原料制备的纳米金刚石及其方法
CN112357918B (zh) * 2020-11-03 2023-08-25 中国林业科学研究院林产化学工业研究所 以植物纤维为原料制备的纳米金刚石及其方法

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