Fig. 7

Synthesis of single-atom Pt/CeO₂ with improved reducibility and its transformation into an active catalyst. The Pt/CeO₂ single-atom catalyst is reduced and forms Pt nanoparticles. This active state of the catalyst readily provides oxygen to react with CO adsorbed on Pt nanoparticles, preventing CO poisoning. Red: ionic Pt, green: metallic Pt