Anchoring Ni3S2/Cr(OH)3 hybrid nanospheres on Ti3C2@NF dual substrates for efficient urea electrolysis by ion exchange

Urea-assisted hydrogen production is an energy-saving protocol, so it is particularly important to develop high-performance non-noble metal urea oxidation reaction (UOR) catalysts in simple ways. Herein, exploiting the surface electronegativity of Ti 3 C 2 , the electrode covering Ti 3 C 2 nanosheets and Ni 3 S 2 /Cr(OH) 3 nanospheres were synthesized on a nickel foam substrate by electrostatic adsorption and ion exchange for the first time, and both steps were completed within 2 hours at room temperature. The required overpotential are 130 mV and 169 mV at 10 mA·cm − 2 for UOR and hydrogen evolution reaction(HER), respectively. It delivers current density of 10 mA·cm − 2 at 1.52 V in a two-electrode system, and shows excellent stability. The superior performance of electrodes is mainly attributed to the synergy between the Ni 3 S 2 crystals and the Cr(OH) 3 amorphous structure, as well as the large adsorption surface and excellent electrical conductivity provided by the double substrate formed by the uniform coverage of Ti 3 C 2 on NF. The mild preparation process contributes excellent electrode stability to the protection of nickel foam structure. The ingenious structural design of Ni 3 S 2 /Cr(OH) 3 -Ti 3 C 2 @NF and the facile preparation method provide ideas for the development of low-cost and efficient electrodes with industrial application prospects.