A (CH3)2CNHCH3PbBr3/CH3NH3PbBr3 core–shell heterostructure fabricated by an in situ a-site reaction for fast response 1D perovskite photodetectors

Abstract

Benefitting from their long carrier diffusion lengths, low trap densities and high carrier mobilities, metal halide perovskites are of great value in the field of energy and optical communications. Herein, we propose a reversible organic cation reaction for (CH₃)₂CNHCH₃PbBr₃/CH₃NH₃PbBr₃ core–shell microwires (MWs), in which (CH₃)₂CNHCH₃PbBr₃ grow on bulk CH₃NH₃PbBr₃ in acetone and then convert back to CH₃NH₃PbBr₃ on the surface with the action of water. The core–shell MWs present excellent stability for more than 454 days with over 80% humidity.  Moreover, the employed core–shell heterostructure significantly increases the photoluminescence lifetime and improves the rise/recovery response. The (CH₃)₂CNHCH₃PbBr₃/CH₃NH₃PbBr₃ core–shell heterostructure demonstrates excellent stability and fast response (2.8 ms/0.8 ms), which is anticipated to find comprehensive applications in future optical communication of one-dimensional devices.