Synthesis of Lead-free CsGeI3 Perovskite Colloidal Nanocrystals and Electron Beam-induced Transformations

Xiaotong Wu; Weidong Song; Qian Li; Xixia Zhao; Dongsheng He; Zewei Quan

doi:10.1002/asia.201800573

Synthesis of Lead-free CsGeI₃ Perovskite Colloidal Nanocrystals and Electron Beam-induced Transformations

Chem Asian J. 2018 Jul 4;13(13):1654-1659. doi: 10.1002/asia.201800573. Epub 2018 May 30.

Authors

Xiaotong Wu^{1

2}, Weidong Song¹, Qian Li¹, Xixia Zhao¹, Dongsheng He³, Zewei Quan¹

Affiliations

¹ Department of Chemistry, Southern University of Science and Technology, SUSTech, Shenzhen, Guangdong, 518055, P. R. China.
² School of Chemical Biology and Biotechnology, Shenzhen Graduate School of Peking University, Shenzhen, Guangdong, 518055, P. R. China.
³ Materials Characterization and Preparation Center, Southern University of Science and Technology, SUSTech, Shenzhen, Guangdong, 518055, P. R. China.

PMID: 29700979
DOI: 10.1002/asia.201800573

Abstract

Colloidal nanocrystals (NCs) of metal halide perovskite have recently aroused great research interest, due to their remarkable optical and electronic properties. We report a solution synthesis of a new member in this category, that is, all-inorganic lead-free cesium germanium iodine (CsGeI₃ ) perovskite NCs. These CsGeI₃ colloidal NCs are confirmed to adopt a rhombohedral structure. Moreover, the electron beam-induced transformations of these lead-free perovskite NCs have been investigated for the first time. The fracture of single-crystalline CsGeI₃ nanocubes occurs first, followed by the emergence and growth of cesium iodine (CsI) single crystals and the final fragmentation into small debris with random orientations. Notably, the electron-reduced Ge species in CsGeI₃ nanocubes exhibit a distinctive transformation path, compared to heavier Pb atoms in lead halide perovskite NCs.

Keywords: electron beam irradiation; germanium; lead-free perovskites; nanocrystals; stability.