Quadruple-cation lead-free perovskite-inspired materials enable high-speed self-powered photodetection

Abstract

High-speed, self-powered photodetectors (PDs) have been demonstrated using quadruple-cation lead-free antimony (Sb)-based perovskite-inspired materials (PIMs). The incorporation of phenylethylammonium iodide (PEAI) into the layered Sb-based PIM layers enhances film morphology and reduces defect density, thereby improving the device performance. As a result, the optimized PIM PDs exhibit a high responsivity of 210 mA W⁻¹, a detectivity on the order of 10¹² Jones, and an ultrafast −3 dB bandwidth of 542 kHz under zero bias, outperforming previously reported A₃B₂X₉-type PIM PDs. Although originally evaluated in a photovoltaic configuration, the devices also exhibit a power conversion efficiency of 1.72% and a high fill factor of 70%, underscoring the effectiveness of PEAI in regulating interfacial and bulk properties. This work highlights PEAI engineering as an effective strategy for advancing the photodetection performance of Sb-based PIM PDs and paves the way for high-speed, self-powered PDs for practical optoelectronic applications.