Low-temperature and high-sensitivity Au-decorated thin-walled SnO2 nanotubes sensor for ethanol detection

The nanostructures of oxides decorated with noble metals have been used to detect ethanol at low temperature with high sensitivity. Instead of traditional thick ones, this work explored the ultrathin SnO2 nanotubes (NTs) decorated with Au nanoparticles (NPs) for chemical gas sensors. The field-emission scanning electron microscopy and field-emission transmission electron microscopy characterized the SnO2 NTs and Au NPs with uniform structures. After that, the X-ray diffraction, X-ray photoelectron spectroscopy and base resistance test proved the existence of the Schottky junction. Then, the gas-sensing test results show that the gold-modified SnO2 NTs sensor has excellent sensing properties such as low operating temperature (25 ℃), high sensitivity (Response value of 192 at 160°C), low detection limit (1 ppm), good selectivity for ethanol, and high stability. This study presents a novel approach for gas sensing using ultrathin SnO2 NTs decorated with Au NPs, which has demonstrated excellent sensing properties. The results of this study provide a foundation for further research and development of highly efficient gas sensors for various applications.