Drastic change in shape of tetragonal TeO2 nanowires and their application to transparent chemical gas sensors

We have synthesized one-dimensional structures of tellurium dioxide (TeO2) by heating of tellurium powders. Their morphology was drastically changed as the growth temperature increased in the range of 400–500 °C, in which high-temperature process facilitated the thickening of the stem nanowires, as well as the growth of secondary branches on the stems. The obtained TeO2 products were crystalline with tetragonal structure. The TeO2 nanowire film exhibited a high transmission rate of about 73%. We have investigated the NO2 sensing properties of the as-fabricated TeO2 nanowires, in which a linear relationship between sensitivity and the NO2 gas concentration was observed. Thus, the TeO2 nanowires demonstrated their potential application to transparent chemical sensors.