Cyclic ether on Pt-based carbon support for enhanced alkaline hydrogen evolution

Abstract

Oxygen functionalization of carbon support has widely been explored for improving the catalytic performance of carbon-supported Pt catalysts (Pt/C) since the existential state of Pt is significantly affected by the surface properties of the carbon support. However, the impact of oxygen functionalization of carbon surface on the catalytic performances of Pt/C catalysts for alkaline hydrogen evolution reaction (HER) has not yet been adequately investigated. Herein, graphite (GP) was used as model support and oxidized through nitric acid to introduce enriched hydroxyl groups, which were further partially converted to cyclic ether in subsequent annealing treatment. The effects of oxygen functionalization of carbon on HER performances of the resulting Pt/C catalysts after loading Pt particles were investigated. The results suggested that Pt loading on oxidized GP followed by treatment at 300 ℃ (Pt/GP-O-300) exhibited much better HER activity and stability than the unmodified (Pt/GP) and only oxidized (Pt/GP-O) samples. Pt/GP-O-300 delivered a lower overpotential of 144 mV at 10 mA cm−2 than Pt/GP (220 mV) and Pt/GP-O (183 mV). The time-dependent current density and accelerating durability testing analyses indicated Pt/GP-O-300 possess better stability than Pt/GP and Pt/GP-O. Overall, novel insights into the design of oxygen functional groups on carbon surface were provided, a promising strategy to enhance HER performance of future prepared Pt/C catalysts.