Interface Modification of Single Atom-Nanocluster Synergistic Sites to Break the Activity-Selectivity-Stability
Zemin Chen1, Chufei Wang1, Boning Zhang2
1Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, Hefei, 230026, China.
None:
Synergistic sites (M1+Mn) integrating single atoms (M1) and clusters (Mn) exhibit tremendous promise for overcoming linear scaling relationships. However, metal entities spatial segregation within synergistic sites impedes the overall optimization and structure-property analysis, and the support interface of the M1 and Mn sites critical for intermediate adsorption-transfer kinetics has yet unexplored. Here, for the first time, interfacial modification strategy is proposed to modulate the interface and electronic structure of M1+Mn sites. This is systematically altered that the interface of Pd1+Pdn sites from hydroxyapatite (HAP) to nitrogen-doped carbon-modified HAP (NC/HAP) and pure NC, with all sites maintaining the comparable size and content. In the semi-hydrogenation of alkynes, volcano-type correlations between Pd1+Pdn sites with varying interfaces and hydrogenation activities are observed, peaking for those supported on NC/HAP. The obtained Pd1+Pdn@NC/HAP exhibits superior activity for alkynol-to-enol conversion, achieving a formation rate up to 3707.7 mol molPd -1 h-1 while maintaining 97.2% selectivity. Comprehensive investigations propose d-band center of Pd1+Pdn sites with different interfaces as a descriptor to elucidate the volcano-type correlation for various selective hydrogenation reactions. Interfacial modification of Pd1+Pdn sites can optimize their electronic structure, adeptly managing substrates adsorption-desorption kinetic and interface H-spillover between segregated metal sites, thereby breaking -the activity-selectivity-stability trade-off.
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