Multidirectional Self-Driven Polarization-Sensitive Photodetection Induced by Asymmetric Contact
Polar two-dimensional (2D) perovskites, with their excellent semiconductor properties, intrinsic anisotropy, and bulk photovoltaic effect, have emerged as promising candidates for self-driven polarization-sensitive photodetectors. However, these self-driven polarized detectors typically require fabrication along the spontaneous polarization direction to maintain device operation in the self-driven mode, which imposes additional limitations. Herein, we demonstrate multidirectional self-driven polarization-sensitive photodetection by constructing 2D perovskite-based asymmetric contact devices, Ag/2D perovskite/C. The built-in electric field, originating from the difference in work functions, acts as the driving force for the separation and transport of photogenerated carriers. Notably, this approach does not necessitate a specific direction, thereby enabling multidirectional self-driven photodetection. Under excitation by linearly polarized light, our devices exhibit impressive polarization-sensitive discrimination in multiple directions, achieving polarization ratios of 3.3 and 3.1 along the a and b-axes, respectively. Our work enriches the approaches enabling self-driven polarization-sensitive photodetection, free from the previous limitations.