Ultralong CH3NH3PbI3 nanowires synthesized by a ligand-assisted reprecipitation strategy for high-performance photodetectors

Abstract

Organic–inorganic hybrid perovskite nanowires with well-defined structures have attracted considerable attention for optoelectronic applications. Perovskite nanowires integrated into practical optoelectronic devices are often hindered by the poor crystalline quality. Herein, a ligand-assisted reprecipitation (LARP) strategy is employed to prepare ultralong and freestanding CH₃NH₃PbI₃ nanowires on a large-scale. Oleylamine is adopted as an inhibitor, which can create a passivation layer on the surface of CH₃NH₃PbI₃, to slow down the crystallization rate of CH₃NH₃PbI₃ nanowires. With the low crystallization rate, several millimeters long and high-quality CH₃NH₃PbI₃ nanowires with smooth surfaces can be synthesized on a large scale. Photodetectors fabricated on oleylamine assisted synthesized CH₃NH₃PbI₃ nanowires exhibit high detectivity, which is five times higher than that of non-oleylamine assisted synthesized CH₃NH₃PbI₃ nanowire photoanodes.