Photo-mediated co-loading of highly dispersed MnO-Pt on g-CN boosts the ambient catalytic oxidation of formaldehyde.

Exploration of effective metal/support combinations and new fabrication approaches is attractive in the catalytic oxidation of HCHO. In this study, we proposed graphitic carbon nitride (g-C3N4) as a non-metal oxide based support to co-load Pt and MnOx through room-temperature photodeposition and in turn applied for HCHO oxidation. Here, Pt was the active component, while MnOx was the cocatalyst to compensate the shortage of active oxygen on g-C3N4. g-C3N4 was found as a promising support for the high dispersion of Pt and MnOx. Well dispersed Pt nanoparticles with an average diameter of 1.8 nm were obtained, which were highly favorable for the loading of MnOx as MnOx-Pt/g-C3N4. Catalytic performance results indicated that the limited HCHO conversion over g-C3N4 and Pt/g-C3N4 was significantly promoted with the introduction of MnOx, with an optimum MnOx amount of 3.0 wt%. The developed catalysts remained highly stable for 30 h. The enhanced catalytic activity of MnOx-Pt/g-C3N4 was due to the increased number of active oxygen species with the introduction of MnOx and the efficient transfer of electrons from g-C3N4 to Pt. Compared to the traditional impregnation, photodeposition process avoids the application of H2 and high temperatures, scoring in favor of its green and safe nature. This study can concomitantly provide a new way for the design and fabrication of a non-metal oxide based support for the efficient HCHO catalytic oxidation and the application of the photocatalytic process in catalyst fabrication.