Lead Halide Perovskites

Lead Halide Perovskites, LHPs, have shown remarkable promise for use in photovoltaics, photodetectors, light-emitting diodes, and lasers. Although solution-processed polycrystalline films are the most widely studied morphology, LHP nanowires, NWs, grown by vapor-phase processes offer the potential for precise control over crystallinity, phase, composition, and morphology.

In ground-breaking work published in Nano Letters, researchers in the Cahoon Group, in collaboration with the Papanikolas Group and Chapel Hill Analytical & Nanofabrication Laboratory, CHANL, report the first demonstration of self-catalyzed vapor–liquid–solid, VLS, growth of lead halide NWs, and conversion to LHP. This is the first ever report of the vapor-liquid-solid, VLS, growth of PbI2 nanowires. The VLS mechanism is a proven success with other material systems, also developed in the Cahoon lab, but never before has it been seen with lead halides.

This work appears at an opportune time, with interest in lead halide perovskites increasing because of their uncommonly efficient electronic and optoelectronic properties relative to other solution-processable materials. The technique developed in the Cahoon Group for growing lead halide nanowires and converting them to organic-inorganic perovskite nanowires should allow the rational design of nanostructures for various optoelectronic technologies, including potentially unique applications such as hot-carrier solar cells.