Lead-Free Small-Bandgap Cs2CuSbCl6 Double Perovskite Nanocrystals

Wei Zhou; Peigeng Han; Xirui Zhang; Daoyuan Zheng; Songqiu Yang; Yang Yang; Cheng Luo; Bin Yang; Feng Hong; Donghui Wei; Ruifeng Lu; Keli Han

doi:10.1021/acs.jpclett.0c01968

Lead-Free Small-Bandgap Cs₂CuSbCl₆ Double Perovskite Nanocrystals

J Phys Chem Lett. 2020 Aug 6;11(15):6463-6467. doi: 10.1021/acs.jpclett.0c01968. Epub 2020 Jul 28.

Authors

Wei Zhou^{1

2}, Peigeng Han^{2

3}, Xirui Zhang¹, Daoyuan Zheng⁴, Songqiu Yang², Yang Yang², Cheng Luo^{2

3}, Bin Yang², Feng Hong^{2

3}, Donghui Wei⁵, Ruifeng Lu¹, Keli Han^{2

4}

Affiliations

¹ Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094, P. R. China.
² State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, P. R. China.
³ University of the Chinese Academy of sciences, Beijing 100049, P. R. China.
⁴ Institute of Molecular Sciences and Engineering, Shandong University, Qingdao 266237, P. R. China.
⁵ College of Chemistry, Institute of Green Catalysis, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, P. R. China.

PMID: 32697914
DOI: 10.1021/acs.jpclett.0c01968

Abstract

Lead-free halide double perovskites (DPs) have attracted great attention due to their stability, nontoxicity and good photophysical property. In this work, we report a new, small-bandgap Cs₂CuSbCl₆ DP nanocrystals (NCs) with a bandgap of 1.66 eV, which is the smallest bandgap in reported lead-free three-dimensional DP NCs. Density functional theory calculations confirm that Cs₂CuSbCl₆ DP has an indirect bandgap of 1.70 eV, in good agreement with the experimental result. The photophysical property of Cs₂CuSbCl₆ NCs is studied by the combination of femtosecond transient absorption (TA) and nanosecond TA techniques. In addition, the Cs₂CuSbCl₆ NCs exhibit good stability exposed in the air. These results show that these NCs will have great potential to be used as a light-absorbing material for photovoltaic applications.