Two-Dimensional Ruddlesden-Popper Perovskite Cs2PbI2Cl2 Nanostructures for Self-Powered Visible-Blind Ultraviolet Photodetectors

All-inorganic two-dimensional Ruddlesden-Popper perovskite Cs2PbI2Cl2 nanostructures with excellent thermal stability, tunability, and carrier mobility have great potential to be utilized as functional layers in visible-blind ultraviolet photodetectors. In order to achieve efficient devices, we prepare herein Cs2PbI2Cl2 nanostructures using a two-step dipping method and reveal the growth process of the nanostructures from nanowires to films. The morphologies of the intermediate nanosheets and nanosheet/film structures are characterized to investigate their microstructural characteristics and crystallization processes. Furthermore, typical Cs2PbI2Cl2 nanostructures are utilized to construct low cost, simple-structured, self-powered photodetectors. The self-powered champion device based on a Cs2PbI2Cl2 nanosheet/film nanostructure exhibits a peak responsivity of 35.01 mA/W, a specific detectivity of 2.45 x 10(12) Jones, and a short response time of 80 mu s, together with exceptional operational stability in ambient air. The favorable electronic performance is strongly related to the suppressed carrier recombination and enhanced built-in potential.