Acta Phys. -Chim. Sin. ›› 2023, Vol. 39 ›› Issue (1): 2209007.doi: 10.3866/PKU.WHXB202209007

• ARTICLE • Previous Articles    

Halogen Regulation for Enhanced Luminescence in Emerging (4-HBA)SbX5∙H2O Perovskite-Like Single Crystals

Bihao Zhuang1,2, Zicong Jin1,2, Dehua Tian3,4, Suiyi Zhu1,2, Linqian Zeng1,2, Jiandong Fan1,2,4,*(), Zaizhu Lou3,4,*(), Wenzhe Li1,2,*()   

  1. 1 Institute of New Energy Technology, Department of Electronic Science and Engineering, College of Information Science and Technology, Jinan University, Guangzhou 510632, China
    2 Key Laboratory of New Semiconductors and Devices of Guangdong Higher Education Institutes, Jinan University, Guangzhou 510632, China
    3 Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
    4 State Key Laboratory for Crystal Materials, Shandong University, Ji'nan 250100, China
  • Received:2022-09-05 Accepted:2022-09-20 Published:2022-09-29
  • Contact: Jiandong Fan,Zaizhu Lou,Wenzhe Li E-mail:jdfan@jnu.edu.cn;zzlou@jnu.edu.cn;li_wz16@jnu.edu.cn
  • About author:Email: li_wz16@jnu.edu.cn (W.L.)
    Email: zzlou@jnu.edu.cn(Z.L.)
    Email: jdfan@jnu.edu.cn (J.F.)
  • Supported by:
    the National Natural Science Foundation of China(22075103);the National Natural Science Foundation of China(22175076);the Guangdong Basic and Applied Basic Research Foundation for Distinguished Young Scholar(2019B151502030);the Guangdong Basic and Applied Basic Research Foundation for Distinguished Young Scholar(2018B030306004);the Natural Science Foundation of Guangdong Province(2022A1515010489);the Science and Technology Plan Project of Guangzhou(202002030159);the Fundamental Research Funds for the Central Universities(21621112);the State Key Laboratory of Crystal Materials, Shandong University(KF21-03);the "Young Top Talents" in the Pearl River Talent Project of Guangdong Province(2017GC010424)

Abstract:

Luminescent materials have attracted considerable attention because of their extensive applications, for example, in lighting, display, and imaging. As one of the emerging luminescent materials, perovskites have been widely studied and reported. Among them, Pb-based perovskites have shown great promise as their photoluminescence quantum yield (PLQY) is almost 100%. However, the high chemical toxicity and low stability of Pb-based perovskites increase their production costs and limit their practical applications. Sn-based perovskites are also widely studied and their PLQY can reach approximately 90%; however, Sn2+ easily oxidizes to Sn4+ especially upon air exposure. When compared with Pb- and Sn-based perovskites, Sb-based perovskites have the advantages of low chemical toxicity and high thermal stability. Furthermore, the optical properties of Sb-based perovskites have been improved in recent years and are expected to surpass those of Pb- and Sn-based perovskites. Herein, we report a novel series of (4-HBA)SbX5∙H2O single crystals (where 4-HBA is short for 4-hydroxybenzylamine, and X is Cl or Br). High quality single crystals of (4-HBA)SbBr5∙H2O, (4-HBA)SbBr3Cl2∙H2O, and (4-HBA)SbCl5∙H2O with Sb5+ can be prepared via the solvothermal method. The abovementioned three materials belong to the P-1 space group. The halide and hydroxyl ions surrounded by Sb5+ ions in 4-hydroxybenzylamine formed distorted octahedral structures. Based on the results of steady-state fluorescence spectroscopy, excitation spectroscopy, transient fluorescence spectroscopy, fluorescence lifetime imaging, and density functional theory, it was found that the (4-HBA)SbBr5∙H2O single crystal has a direct band gap, whereas the single crystals of (4-HBA)SbBr3Cl2∙H2O and (4-HBA)SbCl5∙H2O have an indirect band gap. When the concentration of Cl in (4-HBA)SbX5∙H2O increased, the band gap increased from 2.99 to 3.58 eV and the photoluminescence wavelength decreased from 618 to 595 nm. The obtained results also showed that the emission of the (4-HBA)SbX5∙H2O single crystal originated from the self-trapping exciton effect. With the introduction of Cl, the size of the [SbX5O]2− octahedron decreased, the exciton shielding reduced, and the exciton absorption was enhanced. Additionally, after replacing Br with Cl, the radiation recombination process of the excited electrons from the Sb5+ ions surrounding the halide ions gradually replaced the electron recombination of the hydroxyl ions, which extended the fluorescence lifetime from 12 to 22 ns and improved the PLQY by a factor of approximately 40.

Key words: Single crystal, Photoluminescence, Sb-based perovskite, Photophysical property, Halogen regulation

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