By coupling a Pt-catalyzed fluorogenic reaction with the Pt-electrocatalyzed hydrogen-oxidation reaction (HOR), CIAC research group led by Prof. XU Weilin combine single-molecule fluorescence microscopy with traditional electrochemical methods to study the real-time deactivation kinetics of a Pt/C electrocatalyst at single-particle level during electrocatalytic hydrogen-oxidation reaction. The decay of the catalytic performance of Pt/C could be mainly attributed to the electrocatalysis-induced etching or dissolution of Pt nanoparticles. They also observed spontaneous regeneration of activity and incubation period of the Pt electrocatalyst at single-particle level. The researchers believed that all these new insights are practically useful for the understanding and rational design of highly efficient electrocatalysts for application in fuel cells.