Study of the catalyst poisoning and reactivation of Pt nanoparticles on the surface of WO3 nanowire in gasochromic coloration

In this paper, we report the degradation of gasochromic coloration performance in Pt-coated WO3 (Pt/WO3) nanowire films when the samples were exposed in air, due to the poisoning of Pt nanoparticles catalyst. The poisoned Pt nanoparticles can be reactivated by annealing in air, suggesting that the degradation originated from the absorption of certain gas species. X-ray photoelectron spectroscopy (XPS) was applied to investigate the gas desorption from poisoned Pt/WO3 nanowire films during the annealing process. Based on the XPS results, a model involving chemical reactions and physical processes on the surface of Pt/WO3 nanowires during annealing was developed to explain the degradation phenomenon.