Enhanced near-UV emission from self-catalytic brush-like GaN nanowires

Recently, the enhanced field emission, photocatalytic activity and blue shift in UV emission of branched GaN nanowire structures were reported. Nevertheless, enhanced luminescence in branched GaN nanowires have not been reported despite the importance of short-wavelength emission. This paper reports synthesis of self-catalytic brush-like GaN nanowires exhibiting enhanced near-ultraviolet (NUV) emission. The diameters of the branches in the brush-like nanowires ranged from 3 to 14nm, whereas those of backbones ranged from 30 to 80nm. In contrast, the diameters of pristine nanowires were in a similar range to those of the backbones in the brush-like nanowires. The brush-like GaN nanowires showed significantly enhanced NUV emission compared to pristine GaN nanowires. This enhanced NUV emission might be due to the quantum confinement of excitons caused by the branches in the brush-like nanowires with diameters smaller than the Bohr exciton radius.