Polar Three-dimensional Organic-inorganic Hybrid Perovskite Realize Highly Sensitive Self-driven Ultraviolet...

Bulk photovoltaic effect (BPVE) triggered by spontaneous polarization in polar organic-inorganic hybrid perovskites (OIHPs) has brought unprecedented development opportunities for self-powered ultraviolet photodetection. However, the currently reported ultraviolet optoelectronic devices are dominated by low-dimensional hybrid perovskites, in which low carrier mobility limits the photoelectric conversion efficiency. Herein, we report for the first time a polar three-dimensional OIHPs, namely MHyPbBr₃ (1, MHy=methylhydrazine), that achieves high-performance self-driven ultraviolet photodetection. Benefitting from the large spontaneous polarization and excellent semiconductor attributes, 1 exhibits 0.33 V BPVE and high carrier mobility lifetime product (μτ) of 1.972×10^-3 cm^-2 V^-1 under ultraviolet illumination. Notably, such merits contribute to efficient self-driven photodetection, where responsivity (R) and detectivity (D*) reach up to 198 mA W^-1 and 1.42×10¹³ Jones, surpassing most reported ultraviolet photodetectors. Furthermore, based on the reversible phase transition of 1, we have achieved controllable ultraviolet photoelectric detection. This work will shed light on the fabrication of high-response self-driven ultraviolet optoelectronic devices.