Light-induced synthesis of ultrafine platinum/porous nitrogen-doped hollow carbon spheres catalyst for efficient methanol oxidation

This study constructed an electrocatalyst of ultrafine platinum nanoparticles (UPt NPs) loaded onto nitrogen-rich porous hollow carbon spheres (NC). Using ZnO as a sacrificial template, NC carriers with a high specific surface area (516.4 m 2 /g) and hierarchical pore structure were prepared via ZIF-8 coating and carbonization. Pyridine/pyrrole nitrogen doping significantly enhanced the strong mutual interaction (SMSI) between Pt and the carrier. Combined with a mild photo-induced approach, the hydrolysis pathway of the Pt precursor was controlled by adjusting the light wavelength (UV/blue-violet/green light), enabling in situ reduction of Pt on the NC surface and within its pore network at room temperature while effectively suppressing agglomeration. Electrochemical testing revealed that the NC/Pt-UV2 catalyst, synthesized using 2 mM Pt precursor combined with UV light, exhibited a mass-specific activity (1179.5 mA·mg Pt −1 ) and electrochemically active area (135.8 m 2  g −1 ) 4.96 and 5.17 times higher than commercial Pt/C, respectively, with superior activity retention compared to Pt/C after 3600 s of constant-potential testing. This work proposes a method for preparing nitrogen-rich hollow carbon spheres with high specific surface area and a novel strategy for the green, efficient synthesis of ultrafine Pt nanoparticles, offering new insights for the design of supported electrocatalysts.