中国物理B ›› 2017, Vol. 26 ›› Issue (9): 96301-096301.doi: 10.1088/1674-1056/26/9/096301

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

First-principles investigations on the mechanical, thermal,electronic, and optical properties of the defect perovskites Cs2SnX6 (X= Cl, Br, I)

Hai-Ming Huang(黄海铭), Zhen-Yi Jiang(姜振益), Shi-Jun Luo(罗时军)   

  1. 1 Shaanxi Key Laboratory for Theoretical Physics Frontiers, Institute of Model Physics, Northwest University, Xi'an 710069, China;
    2 School of Science, Hubei University of Automotive Technology, Shiyan 442002, China
  • 收稿日期:2017-03-29 修回日期:2017-05-22 出版日期:2017-09-05 发布日期:2017-09-05
  • 通讯作者: Zhen-Yi Jiang E-mail:jiangzy@nwu.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 51572219 and 11447030), the Natural Science Foundation of Shaanxi Province of China (Grant No. 2015JM1018), and Graduate's Innovation Fund of Northwest University of China (Grant No. YJG15007).

First-principles investigations on the mechanical, thermal,electronic, and optical properties of the defect perovskites Cs2SnX6 (X= Cl, Br, I)

Hai-Ming Huang(黄海铭)1,2, Zhen-Yi Jiang(姜振益)1, Shi-Jun Luo(罗时军)2   

  1. 1 Shaanxi Key Laboratory for Theoretical Physics Frontiers, Institute of Model Physics, Northwest University, Xi'an 710069, China;
    2 School of Science, Hubei University of Automotive Technology, Shiyan 442002, China
  • Received:2017-03-29 Revised:2017-05-22 Online:2017-09-05 Published:2017-09-05
  • Contact: Zhen-Yi Jiang E-mail:jiangzy@nwu.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 51572219 and 11447030), the Natural Science Foundation of Shaanxi Province of China (Grant No. 2015JM1018), and Graduate's Innovation Fund of Northwest University of China (Grant No. YJG15007).

摘要:

The mechanical properties, thermal properties, electronic structures, and optical properties of the defect perovskites Cs2SnX6 (X=Cl, Br, I) were investigated by first-principles calculation using PBE and HSE06 hybrid functional. The optic band gaps based on HSE06 are 3.83 eV for Cs2SnCl6, 2.36 eV for Cs2SnBr6, and 0.92 eV for Cs2SnI6, which agree with the experimental results. The Cs2SnCl6, Cs2SnBr6, and Cs2SnI6 are mechanically stable and they are all anisotropic and ductile in nature. Electronic structures calculations show that the conduction band consists mainly of hybridization between the halogen p orbitals and Sn 5s orbitals, whereas the valence band is composed of the halogen p orbitals. Optic properties indicate that these three compounds exhibit good optical absorption in the ultraviolet region, and the absorption spectra red shift with the increase in the number of halogen atoms. The defect perovskites are good candidates for probing the lead-free and high power conversion efficiency of solar cells.

关键词: first-principles calculation, perovskites, elastic properties, optical properties

Abstract:

The mechanical properties, thermal properties, electronic structures, and optical properties of the defect perovskites Cs2SnX6 (X=Cl, Br, I) were investigated by first-principles calculation using PBE and HSE06 hybrid functional. The optic band gaps based on HSE06 are 3.83 eV for Cs2SnCl6, 2.36 eV for Cs2SnBr6, and 0.92 eV for Cs2SnI6, which agree with the experimental results. The Cs2SnCl6, Cs2SnBr6, and Cs2SnI6 are mechanically stable and they are all anisotropic and ductile in nature. Electronic structures calculations show that the conduction band consists mainly of hybridization between the halogen p orbitals and Sn 5s orbitals, whereas the valence band is composed of the halogen p orbitals. Optic properties indicate that these three compounds exhibit good optical absorption in the ultraviolet region, and the absorption spectra red shift with the increase in the number of halogen atoms. The defect perovskites are good candidates for probing the lead-free and high power conversion efficiency of solar cells.

Key words: first-principles calculation, perovskites, elastic properties, optical properties

中图分类号:  (First-principles theory)

  • 63.20.dk
71.20.-b (Electron density of states and band structure of crystalline solids) 87.19.rd (Elastic properties) 78.40.Fy (Semiconductors)