SYNTHESIS, STRUCTURE, AND LUMINESCENCE PROPERTIES OF ZnSnO₃ NANOWIRES

Abstract

ZnSnO 3 nanowires were synthesized on Si substrates by thermal evaporation of a mixture of ZnO, SnO 2 and graphite powders. The nanowires were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The ZnSnO 3 nanowires varied from 10 to 100 nm in diameter and up to a few hundred of micrometers in length. Transmission electron microscopy and X-ray diffraction revealed that the nanowires are multiphase nanostructures containing ZnSnO 3 , Zn 2 SnO 4 , ZnO, and SnO 2 phases. Photoluminescence measurements showed that ZnSnO 3 nanowires had a sharp ultraviolet emission peak at approximately 375 nm as well as a broad green emission band centered at approximately 510 nm. The violet emission of ZnSnO 3 nanowires exhibits a blue shift by approximately 5 nm compared to that of ZnO nanowires and the visible emission of ZnO nanowires shifted from the orange region to the green region, which should be attributed to the narrowing of E g . Thermal annealing enhanced the green emission but degraded the ultraviolet emission of the ZnSnO 3 nanowires. In addition, the origin of the enhanced luminescence of ZnSnO 3 nanowires compared to ZnO and SnO 2 nanowires is discussed.