Ultra‐Long Crystalline Red Phosphorus Nanowires from Amorphous Red Phosphorus Thin Films

Heating red phosphorus in sealed ampoules in the presence of a Sn/SnI₄ catalyst mixture has provided bulk black phosphorus at much lower pressures than those required for allotropic conversion by anvil cells. Herein we report the growth of ultra‐long 1D red phosphorus nanowires (>1 mm) selectively onto a wafer substrate from red phosphorus powder and a thin film of red phosphorus in the present of a Sn/SnI₄ catalyst. Raman spectra and X‐ray diffraction characterization suggested the formation of crystalline red phosphorus nanowires. FET devices constructed with the red phosphorus nanowires displayed a typical I–V curve similar to that of black phosphorus and a similar mobility reaching 300 cm² V^?1 s with an I_on/I_off ratio approaching 10². A significant response to infrared light was observed from the FET device.