Study on sensing properties of Pt/Fe/Zn decorated SnO2 sensor for dissolved CO in transformer oil

Online monitoring of dissolved carbon monoxide (CO) in transformer oil plays a significant role in transformer condition assessment and fault diagnosis. In this study, Pt, Fe and Zn decorated SnO₂ nanostructures were successfully synthesized via a simple hydrothermal method. The prepared samples were characterized by X-ray powder diffraction, energy dispersive spectroscopy and field-emission scanning electron microscopy, respectively. Gas sensors were fabricated and CO sensing performances were systematically measured. The Pt doped SnO₂ sensor exhibits enhanced sensing properties than those of pure, Fe and Zn doped sensors. Moreover, a theoretical calculation based on the first-principles was conducted. A large number of electrons was found between Pt doped SnO₂ and CO gas molecule. Theoretical calculations verify the gas sensing results. It provides us a feasible way to explore high-performance CO gas sensor by doping modification.