Conjugated Base Assists Proton Stripping off Pt for Alkaline H ₂ Electrooxidation

Abstract

Abstract Recent studies have revealed that slow transfer of the continuously formed H + away from Pt surface can be a potential cause responsible for the extremely sluggish alkaline hydrogen oxidation (HOR). Herein, we show that anchoring mild oxyacid on carbon support is a generally effective approach to boost interfacial transfer of proton away from Pt. In alkaline solution, the surface anchored oxyacid is deprotonated generating affluent conjugated base surrounding Pt; taking C‐PO 4 2‐ as a typical example, the conjugated base can readily seize the as‐formed H + around Pt (Pt‐H + + C─PO 4 2‐ → Pt + C─H 2 PO 4 ) from HOR, which then are neutralized immediately by OH − in the bulk solution (C─H 2 PO 4  + OH − → C─PO 4 2− + H 2 O). Via such repetitive protonation and deprotonation, the as‐formed H + from HOR is efficiently transported away from Pt surface, thereby significantly improving the HOR rates. This strategy is found both effective for developing home‐made Pt electrocatalysts as well as for modification of those commercial Pt/C. This study emphasizes the importance of enhancing interfacial proton transfer along the pursuit of efficient Pt electrocatalysts for alkaline HOR and provides a straightforward and generally effective strategy to address the issue.