Pt nanoclusters anchored on ordered macroporous nitrogen-doped carbon for accelerated water dissociation toward superior alkaline hydrogen production

Abstract

Developing effective electrocatalysts with reduced Pt content for fast hydrogen evolution reaction (HER) kinetics toward efficient and stable hydrogen production in alkaline media is highly desirable but rather challenging. Herein, Pt nanoclusters (∼1.6 nm) uniformly anchored on ordered macroporous nitrogen-doped carbon support (Pt-30/NCM) with only 3.39 wt% Pt loading is rationally constructed via a polystyrene spheres (PS) template method followed by an impregnating method as a highly enhanced electrocatalyst for alkaline HER. Benefiting from the enhanced mass and charge transport via the ordered macroporous carbon structure as well as the strong metal-support interaction between Pt nanoclusters and nitrogen-doped carbon framework, Pt-30/NCM exhibits superior intrinsic activity and operation stability compared to the solid counterpart without ordered macropores (Pt-30/NCS), even affording a more than 10 times higher mass activity and much better operation stability after 3000 cycles than those of commercial 20 wt% Pt/C. The density functional theory (DFT) calculations reveal that the strong coupling between Pt nanoclusters and nitrogen-doped carbon support can induce favorable charge transfer for accelerated water dissociation as well as desirable d-band center position for suitable adsorption and desorption of alkaline HER intermediates, thus contributing to remarkably improved kinetics of hydrogen production.