Ab initio thermodynamics studies on the phase stability of PtO2 under ambient and high-pressure conditions

doi:10.1016/j.commatsci.2020.109708

HFCAS OpenIR

	Ab initio thermodynamics studies on the phase stability of PtO2 under ambient and high-pressure conditions
	Chen, Quan 1,2; Yang, Yong1,3
	2020-07-01
发表期刊	COMPUTATIONAL MATERIALS SCIENCE
ISSN	0927-0256
通讯作者	Yang, Yong(yyanglab@issp.ac.cn)
摘要	We studied the structural and thermodynamic properties of platinum dioxide (PtO2) at ambient and high pressures by using ab initio thermodynamics calculations. The Gibbs free energies of two stable phases of PtO2, alpha-PtO2 and beta-PtO2, were calculated, and the latter turns out to be energetically the most stable within a wide range of temperature (0-600 K) and pressure (0-51GPa). To study the thermodynamic stability of PtO2, we have developed a method to effectively calculate the entropy and Gibbs free energies of O-2 molecules at gas phase. Using the free energy data of O-2, that of PtO2 and bulk Pt which are calculated with the quasi-harmonic approximation (QHA) and finite temperature correction, we showed that beta-PtO2 will decompose into Pt and O-2 at around 646 K, comparing well with experimental observation. Based on first-principles calculations and particle-swarm optimization (PSO) method for structure search, we have investigated the high-pressure behavior of PtO2. It is predicted that beta-PtO2 will be transformed to alpha-PtO2 at a pressure of similar to 51 GPa. In addition, we found that temperature plays a minor role in the beta-to-alpha phase transformation.
关键词	Platinum dioxide Ab initio thermodynamics Phase stability High pressure Phase transformation
DOI	10.1016/j.commatsci.2020.109708
关键词[WOS]	CHEMICAL CONSTANT ; CRYSTAL-STRUCTURE ; PLATINUM ; GAS ; BETA-PTO2 ; OXIDES ; FORM
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China[11474285] ; National Natural Science Foundation of China[11534012]
项目资助者	National Natural Science Foundation of China
WOS研究方向	Materials Science
WOS类目	Materials Science, Multidisciplinary
WOS记录号	WOS:000539337000003
出版者	ELSEVIER
引用统计	被引频次：4[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.hfcas.ac.cn:8080/handle/334002/103028
专题	中国科学院合肥物质科学研究院
通讯作者	Yang, Yong
作者单位	1.Chinese Acad Sci, Inst Solid State Phys, Key Lab Mat Phys, Hefei 230031, Peoples R China 2.Anhui Univ, Inst Phys Sci & Informat Technol, Hefei 230601, Peoples R China 3.Univ Sci & Technol China, Grad Sch, Sci Isl Branch, Hefei 230026, Peoples R China
推荐引用方式 GB/T 7714	Chen, Quan,Yang, Yong. Ab initio thermodynamics studies on the phase stability of PtO2 under ambient and high-pressure conditions[J]. COMPUTATIONAL MATERIALS SCIENCE,2020,180.
APA	Chen, Quan,&Yang, Yong.(2020).Ab initio thermodynamics studies on the phase stability of PtO2 under ambient and high-pressure conditions.COMPUTATIONAL MATERIALS SCIENCE,180.
MLA	Chen, Quan,et al."Ab initio thermodynamics studies on the phase stability of PtO2 under ambient and high-pressure conditions".COMPUTATIONAL MATERIALS SCIENCE 180(2020).