Wet-milling synthesis of immobilized Pt/Ir nanoclusters as promising heterogeneous catalysts

Being a typical state of the art heterogeneous catalyst, supported noble metal catalyst often demonstrates enhanced catalytic properties. However, a facile synthetic method for realizing large-scale and low-cost supported noble metal catalyst is strictly indispensable. To this end, by making use of the strong metal–support interaction (SMSI) and mechanochemical reaction, we introduce an efficient synthetic route to obtain ultrafine Pt and Ir nanoclusters immobilized on diverse substrates by wet chemical milling. We further demonstrate the scaling-up effect of our approach by large-scale ball-milling production of Pt nanoclusters immobilized on TiO₂ substrate. The synthesized Pt/Ir@Co₃O₄ catalysts exhibit superior oxygen evolution reaction (OER) performance with only 230 and 290 mV overpotential to achieve current density of 10 and 100 mA·cm⁻², beating the catalytic performance of Co₃O₄ supported Pt or Ir clusters and commercial Ir/C. It is envisioned that the present work strategically directs facile ways for fabricating supported noble metal heterogeneous catalysts.