Flower-like superhydrophilic and superaerophobic B-doped NiMoO4@NF as self-supported electrode for highly efficient hydrogen evolution

Abstract

Designing cost-efficient and high activity electrocatalysts for hydrogen generation is significant for the large-scale and sustainable energy conversion. Herein, non-metallic boron (B) doping strategy was used to prepare self-supported electrode (B-NiMoO4@NF) which possessed flower cluster structure and was rich in oxygen deficient, and the influence of different addition of NaBH4 on catalyst performance was also investigated. Experimental studies showed that with the increase of NaBH4 addition, the morphology and structure of NiMoO4 precursor changed from "cuboid to hollow tubular to porous tubular". At the same times, numerous oxygen defect sites were generated that further increased the catalytic specific surface area and exposed more catalytic active sites. The results of surface wettability test showed that the prepared B-NiMoO4@NF electrodes exhibited superhydrophilic and superaerophobic properties, and B10-NiMoO4@NF electrode showed better HER catalytic performance than commercial Pt/C supported by nickel foam (Pt/C@NF). And it merely required an overpotential of 22.89 mV to achieve the current density of 10 mA cm−2 and the low Tafel slope of 30.08 mV dec−1 in 1.0 M KOH solution. Besides, the electrode also exhibited excellent HER stability at the high current density of the electrode (500 mA cm−2).