Heterogeneous catalytic aldehyde-water shift of benzaldehyde into benzoic acid and hydrogen

The “aldehyde-water shift” (AWS) reaction offers a green and sustainable route for producing carboxylic acids with the concomitant release of hydrogen. However, most current AWS processes rely on homogeneous noble metal-based catalysts, facing significant challenges in the separation and recyclability of catalysts. Herein, we present the Pt nanoparticles deposited on highly defective porous CeO2 nanorods (Pt/PN-CeO2) as highly effective catalysts for the production of carboxylic acids and H2 through the AWS reaction. Isotope investigations have confirmed the occurrence of AWS by tracing the origin of the generated hydrogen with one hydrogen from aldehyde and one hydrogen from water. Further mechanism studies have illustrated that the concentration of oxygen vacancies plays a crucial role in both the activation of the C–H bond in aldehydes and the activation of water. These findings provide valuable insights for designing new catalytic systems by focusing on the construction of heterogeneous catalysts for the AWS reaction.