Lead-free perovskite nanocrystals (NCs) have been extensively investigated as a class of next-generation materials for a variety of optoelectronic applications. Herein, we report a colloidal synthesis of a series of Cs4CuxAg2−2xSb2Cl12 (0 ≤ x ≤ 1) perovskite NCs by means of gradually tuning the materials’ composition. Both experimental results and DFT calculations show that both crystal structure (from cubic double perovskite to monoclinic layered double perovskite) and the corresponding electronic band alignment (from indirect to direct bandgap) can be modulated by composition engineering. The established composition−structure−property relationship is of great importance for further advancing our understandings of this highly promising lead-free perovskite-type material. Furthermore, we demonstrate that the Cs4CuSb2Cl12 layered double perovskite NCs can be solution-processed into high-speed photodetectors with ultrafast photo-response and narrow bandwidth. We expect that this study will stimulate future opportunities in the design and fabrication of novel lead-free perovskite-type NCs for a spectrum of optoelectronic applications.

Colloidal synthesis and phase transformation of lead-free Cs4CuxAg2−2xSb2Cl12 (0 ≤ x ≤ 1) perovskite nanocrystals for ultrafast photodetector applications

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.