Resistive gas sensors based on semiconducting metal oxides are cost-efficient and reliable devices used to detect a large variety of gases and volatile compounds. Their application ranges from industrial and safety applications to health and comfort. The surface species and processes involved in the gas reception mechanism determined the gas sensing properties of the material and are matter of various publications and discussions; however, most experimental works were performed far from application relevant operation conditions. The presented results were obtained by operando spectroscopy, i. e. under realistic operation conditions, and provide new insights in the gas reception mechanism of pristine and platinum loaded tin dioxide.
