Rational construction of highly selective Ni/AuPd interface for partial oxidation of alcohols

The balance between catalytic activity and product selectivity remains a challenge in partial oxidation reactions, because its products are prone to be further oxidized. In this paper, a small amount of Ni was introduced on the surface of the supported AuPd alloy nanoparticles (NPs) as a promoter to construct the Ni/AuPd interface for benzyl alcohol partial oxidation, which helped to improve the selectivity of benzaldehyde. The results showed that the introduction of a small amount of Ni (<0.5 wt%) led to no obvious change of the catalytic activity, but the selectivity of benzaldehyde was greatly improved. When Ni content exceeds 1.0 wt%, the benzyl alcohol conversion decreased significantly. This is mainly because a large amount of Ni led to an obvious aggregation of Pd on the catalyst and a large amount of surface Ni species partially covered the active components, resulting in a low catalytic activity. Introducing a small amount of Ni improved the benzaldehyde selectivity and Ni species presented as NiO and NiOOH on catalyst xNi/AuPd/MCF-H. Theoretical calculation results show that the improved benzaldehyde selectivity was attributed to the easy desorption of benzaldehyde from NiO and NiOOH surfaces.