Advanced and Durable Self-Standing MoC-Mo2C Electrode for Alkaline Hydrogen Evolution in Chlor-alkali Electrolysis

Energy saving is crucial for the modern chlor-alkali industry to reduce its carbon footprint and production cost. Herein, an efficient MoC-Mo2C electrode synthesized in molten salt was reported for the alkaline hydrogen evolution reaction (HER) in a simulated chlor-alkali cell. The MoC-Mo2C electrode displays a low overpotential of 179 mV at 500 mA cm–2, which is much lower than that of a low-carbon steel electrode (η500 = 436 mV) for the HER in chlor-alkali conditions (i.e., 3 M NaOH + 3 M NaCl at 85 °C), and it exhibited high stability within 100 h. Furthermore, the effects of NaOH and NaCl concentrations and operating temperatures on its performance for the HER were systematically investigated. The honeycomb-like porous morphology, good hydrophilicity, and unique electronic structure of the electrode are the reasons for its excellent HER activity and durability. This work extends a novel excellent and cost-affordable self-standing MoC-Mo2C HER electrode for application in the chlor-alkali industry, which would greatly reduce the energy consumption of the process.