Cerium(III) phosphate as a promising support for gold catalysts addressed to selective oxidation of glucose under base-free conditions

Supported gold nanoparticles are widely used active oxidation catalysts, however, their efficiency and stability vastly depend on the type of supports utilized. This study aims to unravel the potential application of cerium(III) phosphate as a new support for gold catalysts for selective oxidation of glucose under base-free conditions. Particular interest was directed to: i) the identification of the key factors that promote high activity of supported gold species, ii) the optimization of reaction conditions to assess the impact of catalyst loading and reaction time/ temperature on the efficiency of glucose oxidation, and iii) the elucidation of the stability of Au/CePO4 catalyst in several reaction cycles. The results show that Au/CePO4 exhibits unique surface properties that enable obtaining of much higher activity of gold species in glucose oxidation compared to other well-known metal oxide-based systems. Precisely, it was found that the TOF value calculated for Au/CePO4 was ca. 2.5 times higher than in the case of Au/CeO2 (TOF = 5846 vs. 2309 h- 1, respectively), and ca. 1.5 times higher than that observed for Au/TiO2 (Mintek, TOF = 3839 h- 1). The presented results facilitate the development of more active and highly selective supported gold catalysts for oxidation of biomass-derived platform molecules (e.g., glucose).