Centimeter-size single crystals of 2D hybrid perovskites for shortwave light photodetection with a low detection limit

Abstract

Two-dimensional (2D) organic–inorganic hybrid perovskite materials have been vigorously developed for shortwave light photodetection due to their strong light absorption and excellent semiconductor properties. However, 2D hybrid perovskites with low detection limits have not been widely studied, which hinders their application in weak shortwave light detection. Herein, sensitive weak shortwave light detection with a low detection limit was achieved in the centimeter-size single crystals of 2D hybrid perovskite (PA)₂PbBr₄ (1, PA = CH₃CH₂CH₂NH₃⁺). Beneficial to centimeter-size high-quality single crystals, 1 exhibits a low defect density of 1.66 × 10¹⁰ cm⁻³ and a low dark current of 2.81 × 10⁻¹² A, which is favorable for photoelectric detection. Importantly, even in the vicinity of the minimum photosensitive light intensity of 2D perovskite of 20 nW cm⁻², the photodetector based on 1 still exhibits a remarkable photoelectric response. Meanwhile, the detector shows an excellent detectivity of 6.08 × 10¹² Jones and responsivity of 91.2 mA W⁻¹. This work demonstrates the promising potential of 2D hybrid perovskites for weak shortwave light detection and provides a new perspective for their future photodetection application.