Stimulating and Stabilizing Ultrafine Pt Clusters on Metalloid Support as Dual‐Site Electrocatalyst in High‐Density Seawater Electrolysis and Anion Exchange Membrane Electrolyzer

Abstract Constructing synergistic dual sites has been well‐recognized as an updated avenue in constructing binary‐component Pt/support compounds such materials undergo undesirable interfacial barriers and complicated synthesis. Here an integration of ultrafine Pt nanocrystals on oxygen‐deficient CoMoO 4 nanosheets is reported that achieved superior alkaline hydrogen evolution reaction (HER) activity (110 mV @ 1000 mA cm −2 ) with a reversed hydrogen deliver effect between bifunctional active sites. With perceptions from comprehensive experimental and theoretical results, the HER process occurs in three steps: pronounced water dissociation capability on CoMoO 4 , facile hydrogen transfer to Pt nanoparticles, and optimized hydrogen desorption on the Pt catalytic site. Thanks to the dual site effect, the Pt/CoMoO 4 catalyst boosts HER activity in alkaline large‐density seawater electrolysis and anion exchange membrane electrolyzer (AEM). This work not only provides a valid intensification strategy aimed at support‐type electrocatalysts but also takes insights into dual‐site mechanisms for high‐performance HER.