Precise Strain‐Regulated Photoresponsivity of 2D CsPbBr ₃ Perovskite Nanostructures

ABSTRACT

The discovery of lead halide perovskite materials has turned the solar energy conversion technology and optoelectronic devices upside down. The quantitatively experimental description on the intrinsic relationships of perovskite materials that correlate with strains and photoresponsivity, however, yet remains unclear. Herein, based on 2D CsPbBr ₃ perovskite single crystals, we investigate the dynamic correlations among the strains, the charge distributions, and the photoresponsivity of 2D perovskite crystals. Via a combined experimental and theoretical study, a linear photocurrent response of 2D CsPbBr ₃ under strain resulted by the change of the Schottky barriers under stains for either favourable or hindered photocarriers transport is revealed, which demonstrates that the photoelectronic properties of the perovskite materials can be precisely tuned by strain engineering to meet diverse requests on the photoreponsivity in different optoelectronic applications. This work sheds some light on the intrinsic relationship between strain and the photoresponsivity of 2D perovskite materials and offers a promising avenue to accurately tune the performance of the materials with a piezo‐photoelectric effect for optoelectronic devices.