Decorating g-CN Nanosheets with TiC MXene Nanoparticles for Efficient Oxygen Reduction Reaction.

One of the major challenges associated with fuel cells is exploring highly efficient and low-cost electrocatalysts for the oxygen reduction reaction (ORR). Herein, the feasibility of using TiC MXene nanoparticles (NPs) to enhance the electrocatalytic activity of g-CN for ORR was investigated. By varying the content of TiC NPs, a series of g-CN/TiC heterostructures were obtained, displaying enhanced electrocatalytic activity, including a positive shift in both onset and peak potentials toward ORR, compared to the original g-CN in basic solution. We attribute the improvement to the favorable electrical conductivity of well-dispersed TiC MXene nanoparticles and also enhanced O adsorption due to the electronic coupling effect between g-CN and TiC in the heterostructures. This work demonstrates the potential of earth-abundant MXene family materials to construct low-cost and high-performance electrocatalysts.