Enhanced Photostability and Photoluminescence of PbI2 via Constructing Type-I Heterostructure with ZnO

Improving the stability of lead iodide (PbI2), especially photostability, is in crucial demand for the realization of application-level optoelectronic devices. In this regard, deposition of organic polymers on PbI2 as a protective layer is a common strategy to improve its stability, but polymers with low thermal conductivity generally cannot produce the desired effect. Herein, a novel strategy is proposed for improving the photostability of PbI2 at different excitation wavelengths, including 320, 405, and 532nm, via constructing type-I heterostructure with ZnO with high thermal conductivity. In addition, due to the type-I band alignment between PbI2 and ZnO, the photogenerated carriers in ZnO can be transferred to PbI2, resulting in a nearly eightfold photoluminescence enhancement of PbI2 under 320nm laser excitation. The ZnO as a protective layer forming type-I heterostructure is evidenced as a feasible strategy for enhancing the photostability and photoluminescence of PbI2, facilitating the development of practical applications.

Automated summary

Proposing a novel strategy of constructing a type-I heterostructure with high thermal conductivity ZnO improves the photostability of PbI2 at different excitation wavelengths, leading to nearly eightfold enhancement in photoluminescence under 320nm laser excitation. The type-I band alignment between PbI2 and ZnO enables efficient transfer of photogenerated carriers, enhancing the photostability and photoluminescence of PbI2.