Metal halide perovskites exhibit crystalline-like electronic properties and a soft ionic lattice exhibiting low formation/decomposition energies. While detrimental to the longevity of perovskite solar cells, this easily manipulated soft ionic lattice provides a unique opportunity to chemically manipulate the structure with low energy input. Herein, we leverage the low formation energy inherent in metal halide perovskites to reversibly tune the dimensionality (n) of layered Ruddlesden-Popper FAn+1PbnX3n+1 perovskites (FA = formamidinium, X = I,Br; n = number of layers = 1, 2, 3 … ∞) by modulating the strength and number of H-bonds in the system. This mechanism utilizes H-bond donor/acceptor trigger molecules (solvatochromism) or a temperature change (thermochromism) to reversibly shuttle FAX salt pairs between FAn+1PbnX3n+1 domains and adjacent FAX “reservoir” domains. The result are films that can reversibly switch between multiple colors including yellow, orange, red, brown and white/colorless.

Reversible multicolor chromism in layered metal halide perovskites

ACS Spring Meeting 2021

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