Roles of catalytic PtO<inf>2</inf>nanoparticles on nitric oxide sensing mechanisms of flame-made SnO<inf>2</inf>nanoparticles

Abstract

© 2018 Elsevier B.V. In this work, PtO2-loaded SnO2nanoparticles containing 0–2 wt% Pt produced in a single step by flame spray pyrolysis (FSP) technique were systematically evaluated for nitric oxide (NO) detection. Characterizations by various X-ray/electron microscopic and spectroscopic analyses confirmed the formation of PtO2nanoparticles dispersed on SnO2surfaces. The sensing films were fabricated by spin-coating and the gas sensing performances were studied towards NO at the operating temperatures ranging from 25 to 350 °C in dry air. It was found that the optimal Pt concentration of 0.2 wt% led to the highest sensor response of 2640 toward 5 ppm NO at the optimal operating temperature of 150 °C, which was about five times higher than that of unloaded one. In addition, the response rate analysis revealed the highest catalytic activity of PtO2towards NO at 0.2 wt% Pt. Moreover, the PtO2-loaded SnO2sensor offered improved NO selectivity against NO2, NH3, H2S, C2H5OH and H2. Therefore, the incorporation of PtO2to SnO2nanoparticles by FSP is a promising mean to achieve responsive and selective detection of NO and can be useful for various environmental and biomedical applications.