Boron doped diamond synthesized from detonation nanodiamond in a C-O-H fluid at high pressure and high temperature

Journal Article · Fri Dec 15 00:00:00 EST 2017 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2017.08.009· OSTI ID:22742068

Takai, Kazuyuki ^[1]

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1. Hosei University, 184-8584 Tokyo (Japan)

Boron doped diamond (BDD) was synthesized under high pressure and high temperature (HPHT) of 7 GPa, 1230 °C in a short time of 10 s from a powder mixtures of detonation nanodiamond (DND), pentaerythritol C{sub 5}H{sub 8}(OH){sub 4} and amorphous boron. SEM, TEM, XRD, XPS, FTIR and Raman spectroscopy indicated that BDD nano- and micro-crystals have formed by consolidation of DND particles (4 nm in size). XRD showed the enlargement of crystallites size to 6–80 nm and the increase in diamond lattice parameter by 0.02–0.07% without appearance of any microstrains. Raman spectroscopy was used to estimate the content of boron atoms embedded in the diamond lattice. It was found that the Raman diamond peak shifts significantly from 1332 cm{sup −1} to 1290 cm{sup −1} without appearance of any non-diamond carbon. The correlation between Raman peak position, its width, and boron content in diamond is proposed. Hydrogenated diamond carbon in significant amount was detected by IR spectroscopy and XPS. Due to the doping with boron content of about 0.1 at%, the electrical conductivity of the diamond achieved approximately 0.2 Ω{sup −1} cm{sup −1}. Reaction mechanism of diamond growth (models of recrystallization and oriented attachment) is discussed, including the initial stages of pentaerythritol pyrolysis and thermal desorption of functional groups from the surface of DND particles with the generation of supercritical fluid of low-molecular substances (H{sub 2}O, CH{sub 4}, CO, CO{sub 2}, etc.), as well as byproducts formation (B{sub 2}O{sub 3}, B{sub 4}C). - Highlights: • Boron doped diamond BDD synthesized from detonation nanodiamond, C{sub 5}H{sub 8}(OH){sub 4} and boron. • BDD nano/microcrystals are studied by XRD, SEM, TEM, XPS, FTIR, Raman spectroscopy. • Diamond growth and transition to electro-conductive state (0.2 Ω{sup −1} cm{sup −1}) is observed. • Correlations of Raman bands position and width versus boron content are considered. • High-pressure/temperature reaction mechanism (stages, routes, products) is described.

• OSTI ID: 22742068
• Journal Information: Journal of Solid State Chemistry, Vol. 256; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CARBON DIOXIDE
CARBON MONOXIDE
CRYSTAL GROWTH
DIAMONDS
DOPED MATERIALS
ELECTRIC CONDUCTIVITY
FLUIDS
FOURIER TRANSFORM SPECTROMETERS
HYDROCARBONS
INFRARED SPECTRA
LATTICE PARAMETERS
PRESSURE RANGE MEGA PA 10-100
RAMAN SPECTROSCOPY
REACTION KINETICS
SCANNING ELECTRON MICROSCOPY
SYNTHESIS
TEMPERATURE RANGE 0400-1000 K
WATER
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY