Synthesis of Quasi‐Bilayer Subnano Metal‐Oxide Interfacial Cluster Catalysts for Advanced Catalysis

Abstract

Planar metal clusters possess high metal utilization, distinct electronic properties, and catalytic functions from their 3D counterparts. However, synthesis of these materials is challenging due to much elevated surface free energies. Here it is reported that silica supported planar bilayer Pt-CoOx subnano clusters, consisting of approximately one atomic layer of Pt and one CoOx layer on top, can be achieved by employing strong-electrostatic interactions during impregnation and precisely-controlled CoOx coating using atomic layer deposition. Such bilayer structure is unambiguously confirmed by electron microscopy and in situ X-ray absorption fine spectroscopy which is never reported before. This synthetic approach can be extended to another eight permutations of planar metal-oxide subnano clusters. The resulting bilayer catalysts, owing to unique electronic properties and the abundant metal-oxide interfaces created, exhibit excellent catalytic performances in the reactions of preferential oxidation of CO in H2 and selective hydrogenation of acetylene, by showing much higher selectivity and intrinsic activities at least 8 and 48 times greater than those conventional oxide coated 3D metal clusters/nanoparticles, highlighting the advances of bilayer interfacial structure. These findings open a new avenue to design abundant and highly active metal-oxide interfaces for advanced metal catalysis.