Strain-Manipulated Photovoltaic and Photoelectric Effects of the MAPbBr 3 Single Crystal.

Lead halide perovskite materials, such as MAPbBr 3 and MAPbI 3 , show excellent semiconductor properties, and thus, they have attracted a lot of attention for applications in solar cells, photodetectors, etc. Here, a periodic strain can dynamically manipulate the build-in electric field ( E bi ) of the depletion region with piezoelectricity at the Au/MAPbBr 3 interface. As a result, the photovoltaic short-circuit current density ( J sc ) and the open-circuit voltage ( V oc ) are increased by 670 and 82%, respectively, by applying an external strain upon an asymmetric solar-cell-like Au/MAPbBr 3 /Ga structure. Furthermore, the equivalent piezoelectric d 33 values of ∼3.5 pC/N are confirmed in the Au/MAPbBr 3 /Au structure with both the sinusoidal strain and the 405 nm light illumination with 220 mW/cm 2 upon one semitransparent Au electrode. This study not only proves that pressure can effectively enhance the energy conversion efficiency of the halide perovskite-based solar cells and light detectors but also supposes a multifunctional sensor, which can detect light intensity, sense dynamic pressure, explore accelerated speed, etc. simultaneously.