Synergetic control of Ru/MXene 3D electrode with superhydrophilicity and superaerophobicity for overall water splitting

Synergetic control of active sites, electrolyte wetting and gas releasing is of vital importance for efficient electrocatalysts in water-splitting. Herein, a Ru/MXene 3D electrode, featuring both superaerophobicity and superhydrophilicity, is first synthesized on porous Ni foam with the aid of Ti3C2Tx nanosheets. The Ru/c-Ti3C2Tx/ NF achieves the current densities of 10, 100, 500, 1000 mA/cm2 at overpotentials of 37, 113, 219 and 320 mV respectively, with the Tafel slope of 60 mV/dec for hydrogen evolution reaction in alkaline media. It remains stable at 100 mA/cm2 during continuous electrolysis of 12 h. The Ru/c-Ti3C2Tx/NF demonstrates excellent overall water splitting performance, affording a low voltage of 1.53 V at 10 mA/cm2. In combination with DFT calculation, it illustrates that the enhanced HER performance of Ru/c-Ti3C2Tx/NF attributes to the synergetic modulation of Ru and Ti3C2Tx in the process of H2O dissociation and subsequent H2 formation, as well as superior wettability and rapid gas departure.