2D Ruddlesden–Popper Polycrystalline PerovskitePyro‐Phototronic Photodetectors

Abstract

AbstractTwo‐dimensional (2D) Ruddlesden–Popper (RP) layered halide perovskite has attracted wide attentions due to its unique structure and excellent optoelectronic properties. With inserting organic cations, inorganic octahedrons are forced to extend in a certain direction, resulting in an asymmetric 2D perovskite crystal structure and causing spontaneous polarization. The pyroelectric effect resulted from spontaneous polarization exhibits a broad prospect in the application of optoelectronic devices. Herein, 2D RP polycrystalline perovskite (BA)2(MA)3Pb4I13 film with excellent crystal orientation is fabricated by hot‐casting deposition, and a class of 2D hybrid perovskite photodetectors (PDs) with pyro‐phototronic effect is proposed, achieving temperature and light detection with greatly improved performance by coupling multiple energies. Because of the pyro‐phototronic effect, the current is ≈35 times to that of the photovoltaic effect current under 0 V bias. The responsivity and detectivity are 12.7 mA W−1 and 1.73 × 1011 Jones, and the on/off ratio can reach 3.97 × 103. Furthermore, the influences of bias voltage, light power density, and frequency on the pyro‐phototronic effect of 2D RP polycrystalline perovskite PDs are explored. The coupling of spontaneous polarization and light facilitates photo‐induced carrier dissociation and tunes the carrier transport process, making 2D RP perovskites a competitive candidate for next‐generation photonic devices.