Valance electron structure of carbide-diamond interface and catalytic mechanism for diamond synthesis under high-pressur
The metallic films surrounding a synthetic diamond formed under high-pressure and high-temperature (HPHT) in the presence of Fe-based and Ni-based catalysts were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was showed that the carbide was the primary carbon source for the nucleation and growth of diamond. Based on the EET (empirical electron theory in solid and molecules) theory, the valence electron structure of interface between carbide (Fe3C, Ni3C, (Fe, Ni)3C) and diamond was calculated using the bonding length difference (BLD) method. The boundary criterion of Thomas-Fermi-Dirac-Cheng (TFDC): "the electron density being equal on the contacting surfaces of atoms" was applied to analyze the valence structure of carbide-diamond interface. The result based on the calculation valance electron structure is in good accordance with the experimental result. This study is very helpful to reveal the catalytic mechanism of diamond nucleation and growth and design the new catalyst for diamond synthesis.
作 者： GONG Jianhong XU Bin YIN Longwei QI Yongxin LI Li SU Qingcai LI Musen 作者单位： GONG Jianhong,YIN Longwei,QI Yongxin,LI Li,SU Qingcai,LI Musen(School of Materials Science and Engineering, Shandong University, Jinan 250061, China;Shandong Engineering and Technology Research Center of Super-hard Materials, Zoucheng 273500, China)XU Bin(Department of Materials Science and Engineering, Shandong Institute of Architecture and Technology, Jinan 250014, China)
刊 名： 自然科学进展（英文版） SCI 英文刊名： PROGRESS IN NATURAL SCIENCE 年，卷(期)： 2006 16(8) 分类号： O6 关键词： synthetic diamond carbide catalytic mechanism valence electron theory interface