Emission characteristics of diameter controlled SnO2 nanowires

SnO2 nanowires with controlled diameters were grown by chemical vapor deposition process for which four different diameters ranging from 50 to 140 nm were grown by the controlling thickness of gold-thin-films as catalysts. The influence of the diameter-to-thickness ratio as well as the mechanism of its formation was studied. The relationship between photoluminescence intensities and aspect ratio with considering surface effects of SnO2 nanowires was also investigated. The room temperature luminescence intensity was diminished with decreasing the diameter of nanowires due to the increasing surface/volume ratio. The transition energy and emission intensity show abnormal behavior as temperature decreased from room temperature to 5 K. - Highlights: → Diameter of SnO2 nanowires grown by using CVD method can be controlled by changing the thickness of gold film as catalysts. → The yellow emission peak (∼590nm) intensity was found to be proportional to the diameter of the nanowires. → The luminescence peak intensity and energy exhibit non-Arrhenius type temperature dependence. → This is due to the fact that the deep level exciton transition at low temperature transforms to the surface bound exciton transition with increasing temperature.