Effect of Sn dopant on the properties of ZnO nanowires

Sri doped ZnO (SZO) nanowires were fabricated by a vapour-liquid-solid growth process. The reaction temperature for the formation of the nanowires can be reduced to similar to100degreesC due to Sri doping. The growth direction and morphology of SZO nanowires depend on the amount of Sn, which is attributed to the difference in sizes between Zn and Sri atoms. The ultraviolet emission of SZO nanowires varies from 380 to 396 nm since Sri acts as a doubly ionized donor and introduces deep states in the band gap. In addition, the SZO nanowires exhibit significantly Improved field emission characteristics with a turn-on electric field of 0.05 V mum(-1) under a current density of 0.5 mA cm(-2) in comparison with undoped ZnO nanowires. The work function of the SZO nanowire decreases for higher carrier concentrations and the field enhancement factor increases for smaller diameters. Also, the resistance of the SZO nanowire is decreased for the higher Sri mole fraction. Therefore, it is expected that SZO nanowires can be applied in nano-lasers and flat panel displays in the future.