Colloidal BaZrS3 chalcogenide perovskite nanocrystals for thin film device fabrication

Abstract

The theoretical optoelectronic properties of chalcogenide perovskites (e.g., BaZrS₃) are as good as those of halide perovskites (e.g., CH₃NH₃PbI₃). But the fabrication of optoelectronic devices is rarely reported, mainly because researchers still do not know how to prepare good quality thin films of chalcogenide perovskites. Here, we report colloidal BaZrS₃ nanocrystals (NCs, 40–60 nm) and their solution processed thin film transistors. BaZrS₃ NCs are first prepared using a solid-state synthesis route, and the subsequent surface modifications lead to a colloidal dispersion of NCs in both polar N-methyl-2-pyrrolidinone and non-polar chloroform solvents. The NCs exhibit good thermal (15–673 K) and aqueous stability. Colloidal BaZrS₃ NCs in chloroform are then used to make field effect transistors showing ambipolar properties with a hole mobility of 0.059 cm² V⁻¹ s⁻¹ and an electron mobility of 0.017 cm² V⁻¹ s⁻¹. This report of solution processed chalcogenide perovskite thin films with reasonable carrier mobility and optical absorption and emission is expected to pave the way for future optoelectronic devices of chalcogenide perovskites.