Co3O4-nanoparticle-entrapped nitrogen and boron codoped mesoporous carbon as an efficient electrocatalyst for hydrogen evolution

Abstract

Co₃O₄-nanoparticle-entrapped nitrogen and boron codoped mesoporous carbon was synthesized via the molten salt method. Melamine formaldehyde resin (MF resin) was used as the nitrogen and carbon precursor, and boric acid was utilized as the boron precursor. Furthermore, cobalt chloride was used as the cobalt precursor and the template for the formation of mesopores, which could also be removed and partly recovered by acid washing. The characterization results revealed that the as-obtained samples possessed mesoporous structures, with high cobalt, boron, and nitrogen content values. For the sample of Co_0.65B_0.3NC₈₀₀, the atomic content values of Co, N, and B are 2.3%, 8.87%, and 8.67%, respectively. Moreover, the carbonation temperature and the amount of salt template could both affect the mesoporous structures of the final samples and then affect the electrocatalytic activities for the hydrogen evolution reaction (HER). When the carbonation temperature was 800 °C, the sample of Co_0.65B_0.3NC₈₀₀ showed superior performance for the HER under basic conditions, with high current density, low overpotential, and good stability.