Decorating g-C₃N₄ Nanosheets with Ti₃C₂ 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 Ti₃C₂ MXene nanoparticles (NPs) to enhance the electrocatalytic activity of g-C₃N₄ for ORR was investigated. By varying the content of Ti₃C₂ NPs, a series of g-C₃N₄/Ti₃C₂ heterostructures were obtained, displaying enhanced electrocatalytic activity, including a positive shift in both onset and peak potentials toward ORR, compared to the original g-C₃N₄ in basic solution. We attribute the improvement to the favorable electrical conductivity of well-dispersed Ti₃C₂ MXene nanoparticles and also enhanced O₂ adsorption due to the electronic coupling effect between g-C₃N₄ and Ti₃C₂ in the heterostructures. This work demonstrates the potential of earth-abundant MXene family materials to construct low-cost and high-performance electrocatalysts.