The effect of irradiation-induced point defects on energetics and kinetics of hydrogen in 3C-SiC in a fusion environment

doi:10.1088/1741-4326/aa6b82

	The effect of irradiation-induced point defects on energetics and kinetics of hydrogen in 3C-SiC in a fusion environment
	Sun, Jingjing 1,2; You, Yu-Wei 1; Hou, Jie 1,2; Li, Xiangyan 1; Li, B. S.3; Liu, C. S.1; Wang, Z. G.3
刊名	NUCLEAR FUSION
	2017-06-01
卷号	57 页码:11
关键词	nuclear fusion irradiation-induced point-defects 3C-SiC first-principles
ISSN号	0029-5515
DOI	10.1088/1741-4326/aa6b82
英文摘要	3C-SiC is a promising candidate for structural material of nuclear fusion reactors, and H, T, and D irradiation often causes undesired volume swelling, bubble formation, and degradation of the mechanical properties of the material. However, the underlying mechanisms of these processes are still not well understood. We thereby carried out systematical first-principles calculations to investigate the interaction of H with irradiation-induced point defects in 3C-SiC. Our results show that both self-interstitial atoms and vacancies can act as trap sites for H, which can effectively influence the retention of H and its isotopes in 3C-SiC. Selfinterstitial C and Si atoms can trap up to six and five H atoms, respectively. A C vacancy can trap up to eight H atoms with two H-2 molecules formed, while a Si vacancy can trap only four H atoms with no H-2 molecule formation. The accumulation of H atoms in vacancy forming vacancy-hydrogen clusters may act as the nucleation site for bubbles or blisters in 3C-SiC. The accumulation of H in a vacancy can result in the instability of atoms around the vacancy, which may result in the growth of vacancy-hydrogen clusters to blisters or bubbles. Both Si and C vacancies can significantly slow down the diffusion of H, and energy barriers of H diffusion from the Si and C vacancies reach respectively up to 3.40 and 2.13 eV, which are much higher than that in bulk. These results explain why the calculated diffusion activation energy of H in perfect 3C-SiC is much smaller than experimental values. Our results are helpful for understanding the micro-mechanism of H retention and bubble formation experimentally observed in 3C-SiC.
资助项目	National Magnetic Confinement Fusion Program[2015GB112001] ; National Natural Science Foundation of China[11405202] ; National Natural Science Foundation of China[11475229] ; National Natural Science Foundation of China[11505215] ; Center for Computation Science, Hefei Institutes of Physical Sciences ; International Atomic Energy Agency (IAEA)
WOS关键词	MINIMUM ENERGY PATHS ; ELASTIC BAND METHOD ; SILICON-CARBIDE ; STRUCTURAL-MATERIALS ; SADDLE-POINTS ; DIFFUSION ; HELIUM ; ION ; TEMPERATURE ; COMPOSITES
WOS研究方向	Physics
语种	英语
出版者	IOP PUBLISHING LTD
WOS记录号	WOS:000400923400001
资助机构	National Magnetic Confinement Fusion Program ; National Natural Science Foundation of China ; Center for Computation Science, Hefei Institutes of Physical Sciences ; International Atomic Energy Agency (IAEA)
内容类型	期刊论文
源URL	[http://119.78.100.186/handle/113462/24514]
专题	中国科学院近代物理研究所
通讯作者	Li, B. S.
作者单位	1.Chinese Acad Sci, Inst Solid State Phys, Key Lab Mat Phys, POB 1129, Hefei 230031, Peoples R China 2.Univ Sci & Technol China, Hefei 230026, Peoples R China 3.Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China
推荐引用方式 GB/T 7714	Sun, Jingjing,You, Yu-Wei,Hou, Jie,et al. The effect of irradiation-induced point defects on energetics and kinetics of hydrogen in 3C-SiC in a fusion environment[J]. NUCLEAR FUSION,2017,57:11.
APA	Sun, Jingjing.,You, Yu-Wei.,Hou, Jie.,Li, Xiangyan.,Li, B. S..,...&Wang, Z. G..(2017).The effect of irradiation-induced point defects on energetics and kinetics of hydrogen in 3C-SiC in a fusion environment.NUCLEAR FUSION,57,11.
MLA	Sun, Jingjing,et al."The effect of irradiation-induced point defects on energetics and kinetics of hydrogen in 3C-SiC in a fusion environment".NUCLEAR FUSION 57(2017):11.