Bio-inspired micro area concentrated array assisted perovskite photodetector toward weak light imaging

Abstract

Perovskite photodetectors (PVK PDs) have emerged as weak-light imaging devices due to their favorable carrier mobility, induced light absorption, and photoelectric performance. Modifying the optical structure is an effective strategy for improving the light-collecting performance and sensitivity of the device. Here, a designed and fabricated bio-inspired micro-area concentrated perovskite photodetector system with a micro hemisphere structured array exhibits superior capabilities in light harvesting, and achieves excellent PD device electrical performance and weak light imaging. The responsivity (R) and detectivity (D*) of the micro area concentrated PVK PD reach 0.2 A W⁻¹ and 1.37 × 10¹³ Jones, which are 16.4 and 11.7 times higher than that of the pristine material. The on/off ratio of the micro area concentrated PVK PD is up to 1.6 × 10⁴. The micro hemisphere structured array of PD significantly enhances the weak light sensitivity and results in the realization of weak light imaging under 0.64 μW cm⁻².