Constructing Supported Metallic Pt Single Atoms in Molten NaAlCl 4

Supported platinum-group-metal single-atom catalysts (SACs) have garnered widespread attention in heterogeneous catalysis due to their theoretical 100% atomic utilization efficiency. Isolated metal atoms usually exhibit high oxidation states rather than metallic states owing to the coordination with nonmetal atoms in the supports. Despite recent advances in modulating the coordination environments of SACs, achieving metallic state-dominated SACs remains a formidable challenge. Herein, a new configuration of metallic Pt single atoms (Pt⁰) anchored on the CeO₂ support is constructed by introducing a localized Pt-Ce metal-metal coordination at the interface in a molten NaAlCl₄ environment. The extensive Pt─Ce bonding and electron transfer from the support to the Pt atoms ensure the metallic nature of isolated Pt atoms. This work opens up a new avenue for constructing metallic single atoms and enriches the SACs chemistry.