Saturated Vapor-Assisted Growth of Single-Crystalline Organic-Inorganic Hybrid Perovskite Nanowires for High-Performance Photodetectors with Robust Stability.

One-dimensional organic-inorganic hybrid perovskite nanowires (NWs) with well-defined structures can possess superior optical and electrical properties for optoelectronic applications. However, most of the current perovskite NWs are prepared in the air, making the perovskite NWs vulnerable to moisture and resulting in large amounts of grain boundaries (GBs)/surface defects on NWs. Here, we report the use of an isolated growth environment (organic solvent vapor atmosphere), termed saturated vapor-assisted crystallization method, to fabricate high-quality single-crystalline CH3NH3PbI3 NWs. The NWs have smooth surface with few GBs and surface defects because of the elimination of moisture intrusion in the vapor atmosphere. Significantly, photodetectors based on the as-prepared single-crystalline CH3NH3PbI3 NWs demonstrated an extremely high photoresponsivity up to 460 A/W, an ultrafast response time of ∼180 us, a large specific detectivity of 2.6 × 1013 jones, as well as an improved stability in air over 45 days. The device performance is among the best in the CH3NH3PbI3 NW-based devices. Kelvin probe force microscopy investigation further offered an insight into the excellent photoconductive properties of the CH3NH3PbI3 NWs. This work paves the way toward the fabrication of high-performance nano-optoelectronic devices based on the high-quality organic-inorganic hybrid perovskite CH3NH3PbI3 NWs.