Aqueous Synthesis of Methylammonium Lead Halide Perovskite Nanocrystals

Chong Geng; Shu Xu; Haizheng Zhong; Andrey L Rogach; Wengang Bi

doi:10.1002/anie.201802670

Aqueous Synthesis of Methylammonium Lead Halide Perovskite Nanocrystals

Angew Chem Int Ed Engl. 2018 Jul 26;57(31):9650-9654. doi: 10.1002/anie.201802670. Epub 2018 Jul 4.

Authors

Chong Geng¹, Shu Xu¹, Haizheng Zhong², Andrey L Rogach³, Wengang Bi¹

Affiliations

¹ Tianjin Key Laboratory of Electronic Materials and Devices, School of Electronics & Information Engineering, Hebei University of Technology, 5340 Xiping Road, Beichen District, Tianjin, 300401, China.
² Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Materials Science & Engineering, Beijing Institute of Technology, 5 Zhongguancun South Street, Haidian District, Beijing, 100081, China.
³ Department of Materials Science and Engineering, and Centre for Functional Photonics (CFP), City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, China.

PMID: 29878647
DOI: 10.1002/anie.201802670

Abstract

Methylammonium lead halide perovskite nanocrystals offer attractive optoelectronic properties but suffer from fast degradation in the presence of water. In contradiction to this observation, we demonstrate the possibility of a direct aqueous synthesis of CH₃ NH₃ PbX₃ (X=Br or Cl/Br) nanocrystals through the reaction between the lead halide complex and methylamine when the pH is maintained in the range of 0-5. Under these synthetic conditions, the positively charged surface of the perovskite nanocrystals and the proper ionic balance help to prevent their decomposition in water. Additional surface capping with organic amine ligands further improves the photoluminescence quantum yield of the perovskite nanocrystals to values close to 40 %, ensures their stability under ambient conditions for several months, and their photoluminescence performance under continuous 0.1 W mm^-2 405 nm light irradiation for over 250 hours.

Keywords: aqueous synthesis; lead halide complexes; nanomaterials; pH; perovskite phases.