Solvent-free oxidation of benzyl alcohol on N-doped carbon-supported PtBi alloy

Solvent-free oxidation of benzyl alcohol on bimetallic Pt-Bi catalysts supported on activated carbon (AC), carbon black, carbon nanotube, and N-doped carbon (NC) was studied. While the dispersions of both metals significantly increased on all the bimetallic catalysts, the composition and distribution of the metal species were strongly influenced by different supports. The formation of PtBi alloy was favored on most supports except AC, where aggregation of Bi was observed. Moreover, the oxidation activity was found to closely link to the surface Bi:Pt ratios. Extensive optimizations on PtBi/NC catalyst in batch and flow reactors yielded impressive benzaldehyde yields of 86 % and 70 %, respectively, under mild conditions, which are comparable or even superior to the performances of most state-of-the-art catalysts. Notably, a 96-hour continuous test in a trickle-bed reactor demonstrated stable operation without catalyst deactivation, demonstrating the promising industrial potential.