Sulfur-doped gallium phosphide nanowires and their optoelectronic properties

Sulfur-doped gallium phosphide nanowires were synthesized in a high yield by a facile sublimation of ball-milled mixture powders in a confined reaction zone. The nanowires have diameters in the range of 50-200 nm and lengths up to tens of micrometers. They consist of single-crystalline zinc blende structure crystals with a (111) growth direction. Electron energy-loss spectroscopy reveals that the sulfur doping occurs in the uniform forms of the body. Amorphous Ga-O containing a self-catalyst growth mechanism is proposed based on the detailed characterizations. Photoluminescence shows strong visible emissions at room temperature, indicating their potential applications in light sources, laser or light emitting display devices.