an external magnetic field since it contains magnetic Ni particles. Thus, the combination of atomically dispersed metallic atoms and magnetic Ni@G support can pave the way to design more promising catalysts for selective hydrogenation reactions in industrial applications.

A fundamental understanding of the active sites in heterogeneous catalysts is extremely important in the development of effective catalysts. In general, it is difficult to identify the catalytically active sites due to their structural complexity, including the size and specific atomic configurations. In this paper, we prepare different Pt species (single atoms, fully exposed clusters, and nanoparticles) on a nanodiamond/graphene (ND@G) hybrid support to understand their evolution in structure for low-temperature CO oxidation. Remarkably, the atomically dispersed and fully exposed Pt clusters with an ensemble of a few Pt atoms showed the maximum atom utilization of low-coordinated metal sites. As determined by a catalytic performance evaluation, detailed characterizations, and theoretical calculations, the 0.5 wt % Pt n /ND@G catalyst showed a catalytic performance for CO oxidation at low temperature superior to those of single-atom and nanoparticle catalysts, which was attributed to the weakened CO adsorption and facilitated O2 dissociative adsorption on these atomically dispersed and fully exposed Pt cluster catalysts.

Three crystal phases of Pd-B intermetallics, including Pd6B, Pd5B2 and Pd2B, are synthesized, and their phase-dependent catalytic activities toward electrochemical water splitting and Suzuki coupling reaction are studied. In both...