Chemical Origin of the Stability Difference between Copper(I)- and Silver(I)-Based Halide Double Perovskites.


Journal Article

Recently, CuI - and AgI -based halide double perovskites have been proposed as promising candidates for overcoming the toxicity and instability issues inherent within the emerging Pb-based halide perovskite absorbers. However, up to date, only AgI -based halide double perovskites have been experimentally synthesized; there are no reports on successful synthesis of CuI -based analogues. Here we show that, owing to the much higher energy level for the Cu 3d10 orbitals than for the Ag 4d10 orbitals, CuI atoms energetically favor 4-fold coordination, forming [CuX4 ] tetrahedra (X=halogen), but not 6-fold coordination as required for [CuX6 ] octahedra. In contrast, AgI atoms can have both 6- and 4-fold coordinations. Our density functional theory calculations reveal that the synthesis of CuI halide double perovskites may instead lead to non-perovskites containing [CuX4 ] tetrahedra, as confirmed by our material synthesis efforts.

Full Text

Duke Authors

Cited Authors

  • Xiao, Z; Du, K-Z; Meng, W; Mitzi, DB; Yan, Y

Published Date

  • September 2017

Published In

Volume / Issue

  • 56 / 40

Start / End Page

  • 12107 - 12111

PubMed ID

  • 28755410

Pubmed Central ID

  • 28755410

Electronic International Standard Serial Number (EISSN)

  • 1521-3773

International Standard Serial Number (ISSN)

  • 1433-7851

Digital Object Identifier (DOI)

  • 10.1002/anie.201705113


  • eng