TY - JOUR
T1 - Transformation of carbon onions to diamond by low-temperature heat treatment in air
AU - Tomita, Satoshi
AU - Fujii, Minoru
AU - Hayashi, Shinji
AU - Yamamoto, Keiichi
N1 - Funding Information:
Authors are grateful to Dr. Kensuke Akamatsu for the XRD measurement. One of the authors (S. T.) would like to thank the financial support by a Research Fellowship of the Japan Society for the Promotion of Science for Young Scientists. This work is funded by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, Sports and Culture, Japan.
PY - 2000
Y1 - 2000
N2 - We have demonstrated the transformation of spherical carbon onions to diamond by low-temperature heat treatment. Carbon onions were prepared by 1700 °C annealing of diamond nanoparticles. High-resolution transmission electron microscopy (HRTEM) and X-ray diffraction showed that diamond nanoparticles transformed into the carbon onions and no trace of diamond was detected after the annealing. Carbon onions were subsequently heat treated at 500 °C in air. HRTEM images showed that diamond particles several tens of nanometers in diameter as well as the carbon onions coexist after the heat treatment in air. The results suggest that the onions transformed to diamond at a low-temperature under atmospheric pressure without electron and ion irradiation. From detailed HRTEM and electron energy-loss spectroscopy studies, sp3 sites in the onions and oxygen during the heat treatment are considered to play important roles in the transformation without any irradiation.
AB - We have demonstrated the transformation of spherical carbon onions to diamond by low-temperature heat treatment. Carbon onions were prepared by 1700 °C annealing of diamond nanoparticles. High-resolution transmission electron microscopy (HRTEM) and X-ray diffraction showed that diamond nanoparticles transformed into the carbon onions and no trace of diamond was detected after the annealing. Carbon onions were subsequently heat treated at 500 °C in air. HRTEM images showed that diamond particles several tens of nanometers in diameter as well as the carbon onions coexist after the heat treatment in air. The results suggest that the onions transformed to diamond at a low-temperature under atmospheric pressure without electron and ion irradiation. From detailed HRTEM and electron energy-loss spectroscopy studies, sp3 sites in the onions and oxygen during the heat treatment are considered to play important roles in the transformation without any irradiation.
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U2 - 10.1016/S0925-9635(99)00217-4
DO - 10.1016/S0925-9635(99)00217-4
M3 - Conference article
AN - SCOPUS:0033745631
SN - 0925-9635
VL - 9
SP - 856
EP - 860
JO - Diamond and Related Materials
JF - Diamond and Related Materials
IS - 3
T2 - 10th European Conference on Diamond, Diamond-like Materials, Carbon Nanotubes, Nitrides and Silicon Carbide
Y2 - 12 September 1999 through 17 September 1999
ER -