Fe-doped MoS2 nanosheets array for high-current-density seawater electrolysis.

Designing highly active and cost-effective electrocatalysts for seawater-splitting with large current densities is compelling for developing hydrogen energy. Great advancements in hydrogen evolution reaction (HER) have been achieved, but the progress on driving HER in seawater is still limited. Herein, Fe-doped MoS2 nanoshseets array supported by 3D carbon fibers was explored to be an efficient HER electrocatalyst operating in seawater. Strikingly, it exhibited small overpotentials of 119 and 300 mV to reach the current densities of 10 and 250 mA cm-2 in buffered seawater, respectively, both of them are comparable to the best-reported values under similar conditions. Meantime, the catalyst could keep the stable HER activity for 30 h without notable loss. Theoretical calculations revealed that Fe doping increases the S-edge activity. Our work provides a new avenue for designing MoS2-based HER electrocatalysts for industry application.