Surface/interface engineering N-doped carbon/NiS2 nanosheets for efficiently electrocatalytic H2O splitting
A facile and effective method for preparing bifunctional electrocatalyst with enhance activity and stability is desired for hydrogen and oxygen production. In this paper, ion-liquid-like (ILL) nickel-urea (Ni-U) is designed and applied to prepare 2D N-doped carbon/NiS2 (N-C/NiS2) nanohybrids by one-step in-situ pyrolysis synthesis strategy. The fluidity nature of ILL Ni-U benefits the interface coupling of 2D N-C/NiS2 nanohybrid. Due to the synergistic effect between NiS2 and N-carbon with high conductivity, H2O splitting performance of 2D N-C/NiS2 nanohybrids was significantly enhanced in alkaline media. The corresponding two-electrode cell only needs 1.53 V to undertake 10 mA·cm-2 for H2O splitting. Moreover, the resultant 2D N-C/NiS2 nanohybrids exhibit lasting electrochemical endurance with the maintenance of its stability for more than 48 h. The synthetic strategy not only provides a simple and scalable route for constructing 2D hybrid electrocatalysts, but also paves a way to improve the HER/OER activity of sulphides via the surface/interface engineering strategy.