Synergistically coupling of Ni3Mo3C/Mo2C/Ti3C2Tx MXene/N-doped carbon electrocatalyst towards enhanced hydrogen evolution activity

The development of highly active electrocatalysts is of great significance to improve hydrogen production technology and promoting the development of the hydrogen energy economy. Herein, we report an electrocatalyst consisting of bimetallic carbide nanoparticles encapsulating by an N-doped carbon (NC) layer deposited on the multilayer Ti3C2Tx (denoted as Ni3Mo3C/Mo2C/Ti3C2Tx/NC) for hydrogen evolution reaction (HER) using Ti3C2Tx MXene as a conductively catalytic carrier, polyoxometalates (POM) as a soft template, in which bimetallic carbides interact with hybrid carbon. Profiting from the bimetallic character and multi-aperture structure, the Ni3Mo3C/Mo2C/Ti3C2Tx/NC catalyst represents an overpotential of 99 mV in acidic medium and 98 mV in alkaline medium at 10 mA cm−2 with extended durability for 24 h. The turnover frequency (TOF) at 100 mV overpotential for Ni3Mo3C/Mo2C/Ti3C2Tx/NC electrocatalyst is 0.188 s−1. The remarkable catalytic activity for Ni3Mo3C/Mo2C/Ti3C2Tx/NC electrocatalyst can be attributed to the synergistic effects of bimetallic carbides. In addition, the introduction of Ti3C2Tx MXene further strengthened the conductivity of the catalyst as well as accelerated proton transport. Moreover, the protective effect of the porous carbon layer and the adulteration of the N atom increased the active site, resulting in improved HER properties. This simple preassembly-thermal conversion strategy offers a novel approach for the designing of superior electrocatalysts for HER.