Interplay between remote single-atom active sites triggers speedy catalytic oxidation

Abstract

•We propose an electron-delocalized mechanism (EDM) universally present in catalysis •EDM is an electron-transfer-based dynamic interplay between catalytic sites in action •EDM provides a fundamental design strategy to rationally develop efficient catalysts Understanding interaction between active sites in heterogeneous catalysis is a grand challenge, owing to difficulty in extracting information from different active sites. We report a solution to this problem by showing that electron conduction can facilitate direct interplay of distant active sites. By fabricating two single-atom site catalysts (manganese dioxide-encapsulated metallic silver atomic wires) with one or two ending silver atoms of each wire exposed on surfaces, we find that only the catalyst with both ending silver atoms exposed can trigger low-temperature carbon monoxide oxidation, which provides unequivocal evidence that interaction between active sites is possible upon eligible electron conducting. This result indicates that the interaction between active sites might be universally present in catalysis reactions when there is effective communication between the active sites. Understanding interaction between active sites in heterogeneous catalysis is a grand challenge, owing to difficulty in extracting information from different active sites. We report a solution to this problem by showing that electron conduction can facilitate direct interplay of distant active sites. By fabricating two single-atom site catalysts (manganese dioxide-encapsulated metallic silver atomic wires) with one or two ending silver atoms of each wire exposed on surfaces, we find that only the catalyst with both ending silver atoms exposed can trigger low-temperature carbon monoxide oxidation, which provides unequivocal evidence that interaction between active sites is possible upon eligible electron conducting. This result indicates that the interaction between active sites might be universally present in catalysis reactions when there is effective communication between the active sites.