Field emission and photoluminescence of SnO2 nanograss

Two-dimensional SnO2 nanograsses were synthesized on single-crystal Si substrates by catalyst-assisted thermal evaporation. The photoluminescence spectra from the products revealed multipeaks consistent with previous reports, with the exception of a new peak at 574 nm. The large field emission current from SnO2 nanograss was observed at a high turn-on voltage, which is attributed to a shorter length and a wide emitter radius. The formation of SnO2 nanograsses at the low temperature was pursued on the basis of the vapor-liquid-solid mechanism.