A Universal Solid‐Phase Synthetic Strategy for Ultrafine Intermetallic Libraries Confined in Ordered Mesoporous Carbon

Abstract Ordered intermetallic nanocatalysts supported on high‐surface‐area skeletons are of great importance in catalysis and have disclosed notable catalytic activity and stability that are remarkably better than their random alloy counterparts. Ultrafine intermetallic nanocatalysts are synthetically challenging, especially for universal and scaled‐up synthesis, because of inevitable sintering and phase separation under high temperatures that promote atomic alloying and ordering. Herein, a universal solid‐phase and scaled‐up method is reported for synthesizing ultrafine intermetallic nanocatalysts with uniform size distributions and wide compositional spaces confined in ordered mesoporous carbon (OMC) supports, where the strong physical confinement and chemical interaction between metals and sulfur/mesoporous templates remarkably suppress the high‐temperature sintering and phase separation even up to 1000 °C. Libraries of intermetallic nanocatalysts are successfully synthesized including 52 combinations of host platinum/palladium/rhodium with 15 guest elements confined in 4 OMC supports. Taking oxygen reduction and hydrogen evolution reactions as examples, the intermetallic PtFe nanocatalysts hold remarkable performance, whose activities reach up to ten times higher than commercial Pt/C and also are comparable to the best electrocatalysts reported recently. This feasible synthetic strategy offers an intermetallic library spanning from binary to senary materials for industrial synthesis and applications.