Rational Design of Highly Efficient PdIn-InO Interfaces by a Capture-Alloying Strategy for Benzyl Alcohol Partial Oxidation.

Well-dispersed PdIn bimetallic alloy nanoparticles (1-4 nm) were immobilized on mesostructured silica by an in situ capture-alloying strategy, and PdIn-InO interfaces were rationally constructed by changing the InO loading and reduction temperature. The catalytic performance for benzyl alcohol partial oxidation was evaluated, and a catalytic synergy was observed. The Pd-rich PdIn-InO interface is prone to be formed on the catalyst with a low InO loading after being reduced at 300 °C. It was demonstrated that the Pd-rich PdIn-InO interface was more active for benzyl alcohol partial oxidation than In-rich PdIn species, which was likely to be formed at a high reduction temperature (400 °C). The high catalytic activity on the Pd-rich PdIn-InO interface was attributed to the exposure of more Pd-enriched active sites, and an optimized PdIn-InO/Pd assemble ratio enhanced the oxygen transfer during partial oxidation. The density functional theory (DFT) calculation confirmed that the Pd-rich PdIn(111)-InO interface facilitated the activation of oxygen molecules, resulting in high catalytic activity.