H2O2 production from O2 over Pd nanoparticle (NP) co-catalysts-supported BiVO4 was studied. Several deposition methods and conditions (active metal, co-catalyst loading, solution pH) were investigated for catalyst preparation, and the photo-assisted deposition (PAD) of Pd from an aqueous phosphate buffer solution (pH = 7) was found to be optimal, resulting in small and uniform phosphate ion (PO4 3-)-coated Pd NPs being selectively deposited on the reductive surfaces of the BiVO4. This catalyst exhibited better H2O2 production from O2 in the presence of methanol (CH3OH) as a hole scavenger under visible light irradiation than that by the catalysts prepared by the other methods and under other PAD conditions. It is surmised that PO4 3- partially coats smaller Pd NPs with a narrow size distribution on the reductive surfaces of the BiVO4, and that these NPs promote H2O2 generation synergistically by catalyzing the two-electron reduction of O2 while simultaneously inhibiting the four-electron reduction of O2 and the two-electron reduction of H2O2 to H2O.
内容記述
The present work was partially supported by JSPS KAKENHI Grant Number JP16H06046 and JP17H06439, the Kansai University Fund for Supporting Young Scholars (2017).
2017年度関西大学若手研究者育成経費