中国物理B ›› 2025, Vol. 34 ›› Issue (8): 86106-086106.doi: 10.1088/1674-1056/adce9e

所属专题: SPECIAL TOPIC — Structures and properties of materials under high pressure

• • 上一篇    下一篇

Pressure-induced band gap closing of lead-free halide double perovskite (CH3NH3)2PtI6

Siyu Hou(侯思羽)1, Jiaxiang Wang(王家祥)1, Yijia Huang(黄乙甲)1, Ruijing Fu(付瑞净)2,†, and Lingrui Wang(王玲瑞)1,‡   

  1. 1 Key Laboratory of Materials Physics, Ministry of Education, School of Physics, Zhengzhou University, Zhengzhou 450001, China;
    2 School of Applied Physics and Materials, Wuyi University, Jiangmen 529020, China
  • 收稿日期:2025-02-27 修回日期:2025-04-17 接受日期:2025-04-21 出版日期:2025-07-17 发布日期:2025-07-21
  • 通讯作者: Ruijing Fu, Lingrui Wang E-mail:ruijingfu_wyu@163.com;wanglr@zzu.edu.cn
  • 基金资助:
    This work was supported by the National Natural Science Foundation of China (Grant No. 12474414), the Natural Science Foundation of Henan (Grant No. 242300421157), and the ADXRD measurement was performed at the 4W2 beamline, the Beijing Synchrotron Radiation Facility (BSRF).

Pressure-induced band gap closing of lead-free halide double perovskite (CH3NH3)2PtI6

Siyu Hou(侯思羽)1, Jiaxiang Wang(王家祥)1, Yijia Huang(黄乙甲)1, Ruijing Fu(付瑞净)2,†, and Lingrui Wang(王玲瑞)1,‡   

  1. 1 Key Laboratory of Materials Physics, Ministry of Education, School of Physics, Zhengzhou University, Zhengzhou 450001, China;
    2 School of Applied Physics and Materials, Wuyi University, Jiangmen 529020, China
  • Received:2025-02-27 Revised:2025-04-17 Accepted:2025-04-21 Online:2025-07-17 Published:2025-07-21
  • Contact: Ruijing Fu, Lingrui Wang E-mail:ruijingfu_wyu@163.com;wanglr@zzu.edu.cn
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (Grant No. 12474414), the Natural Science Foundation of Henan (Grant No. 242300421157), and the ADXRD measurement was performed at the 4W2 beamline, the Beijing Synchrotron Radiation Facility (BSRF).

摘要: Lead-free halide double perovskites have recently attracted significant attention due to their exceptional stability and favorable band gaps, making them promising candidates for solar cell applications. However, the relationship between their structural characteristics and intrinsic band gap remains under-explored. This study presents a method to investigate the structure-band gap correlation in a typical halide double perovskite, MA$_{2}$PtI$_{6}$ (MA$^{+} =$CH$_{3}$NH$_{3}^{+}$), using high pressure techniques. The band gap of MA$_{2}$PtI$_{6}$ is effectively reduced at two different rates of 0.063 eV/GPa and 0.079 eV/GPa before and after 1.2 GPa, and progressively closes as pressure further increases. These optical changes are closely related to the pressure induced structural evolution of MA$_{2}$PtI$_{6}$. Moreover, a phase transition from trigonal ($R$-3$m$) to monoclinic ($P$2/$m$) occurs at 1.2 GPa and completes by 2.0 GPa, driven by pressure-induced distortion of the [PtI$_{6}$]$^{2-}$ octahedra, which is responsible for the variation of the band gap. These promising findings pave the way for potential applications in the structural and band gap tuning of halide double perovskites.

关键词: halide double perovskites, high pressure, band gap closing, phase transition

Abstract: Lead-free halide double perovskites have recently attracted significant attention due to their exceptional stability and favorable band gaps, making them promising candidates for solar cell applications. However, the relationship between their structural characteristics and intrinsic band gap remains under-explored. This study presents a method to investigate the structure-band gap correlation in a typical halide double perovskite, MA$_{2}$PtI$_{6}$ (MA$^{+} =$CH$_{3}$NH$_{3}^{+}$), using high pressure techniques. The band gap of MA$_{2}$PtI$_{6}$ is effectively reduced at two different rates of 0.063 eV/GPa and 0.079 eV/GPa before and after 1.2 GPa, and progressively closes as pressure further increases. These optical changes are closely related to the pressure induced structural evolution of MA$_{2}$PtI$_{6}$. Moreover, a phase transition from trigonal ($R$-3$m$) to monoclinic ($P$2/$m$) occurs at 1.2 GPa and completes by 2.0 GPa, driven by pressure-induced distortion of the [PtI$_{6}$]$^{2-}$ octahedra, which is responsible for the variation of the band gap. These promising findings pave the way for potential applications in the structural and band gap tuning of halide double perovskites.

Key words: halide double perovskites, high pressure, band gap closing, phase transition

中图分类号:  (Crystallographic aspects of phase transformations; pressure effects)

  • 61.50.Ks
62.50.-p (High-pressure effects in solids and liquids) 78.40.Fy (Semiconductors)