High-performance flexible and self-powered perovskite photodetector enabled by interfacial strain engineering

Metal halide perovskites (MHPs) with excellent optoelectronic properties, a soft lattice and low-temperature solution processing have become promising candidates for flexible and self-powered photodetectors (FSPPDs) which exhibit tremendous potential for wearable and portable applications. Herein, we demonstrated a strategy to regulate the lattice strain by incorporating an extra hole transport layer (HTL) toward developing a high-performance perovskite-based FSPPD. The modified perovskite (MAPbI(3-x)Cl(x)) film is compressively strained along the out-of-plane direction in comparison with the control film, according to XRD analysis. Consequently, the spin-orbit coupling (SOC) strength enhances in the perovskite film owing to the strain modulation, confirmed by the linearly/circularly polarized photoexcitation-modulated photocurrent and magneto-photocurrent measurements. The enhancement of SOC induces enlarged the Rashba effect, resulting in a prolonged carrier lifetime. Finally, the consequential MAPbI(3-x)Cl(x)-based FSPPD manifests a remarkable improvement in the device performance with a maximum responsivity of 0.39 A W-1 and detectivity of 2.31 x 10(13) Jones at 660 nm.

Automated summary

By incorporating an extra hole transport layer (HTL), the strain of the perovskite film can be regulated and improved to achieve high-performance flexible and self-powered photodetectors (FSPPDs), with potential applications in wearable and portable devices.