The surface coating of metal nanoparticles resulting into core-shell structures is expected to improve the physicochemical properties of the nanoparticle cores without changing their size and shape. Here, we developed a novel strategy to coat Au, AuPd or Pt catalyst cores having average sizes smaller than 2.5 nm, which were pre-synthesized in ionic liquids by corresponding metal sputtering, with an extremely thin In2O3 layer (ca. <1.5 nm) by sputter deposition of indium in a room-temperature ionic liquid. The metal cores of Au or AuPd in core-shell particles exhibited superior stability against heat treatments or during electrocatalytic reactions compared to the corresponding bare metal particles. The In2O3 shell coating considerably enhanced the durability of electrocatalytically active Pt particles (1.2 nm). This sequential metal sputter deposition of different metals in ionic liquids will considerably contribute to the exploitation of key nanostructured components for next-generation energy-conversion systems.
ASJC Scopus subject areas
- 化学 (全般)