Doped-nitrogen enhanced the performance of Nb2CTx on the electrocatalytic synthesis of H2O2

Electrochemical oxygen reduction reaction (ORR) for preparing hydrogen peroxide (H2O2) is a promising way to replace the anthraquinone method. The key to H2O2 production is the development of catalysts to regulate the oxygen reduction reaction pathway. Here, nitrogen-doped Nb(2)CTx was prepared by NH3 annealing method. Compared with precursor Nb2AlC (67.01%) and pure Nb(2)CTx (75.70%), nitrogen-doped Nb2CTx exhibited excellent performance for 2e(-) ORR with > 90% H2O2 selectivity (at 0.4 V vs. reversible hydrogen electrode (RHE)). Faradic efficiency of nitrogen-doped Nb(2)CTx reached 80.75%, whereas those for Nb2AlC and Nb(2)CTx were 60.35% and 39.27%, respectively. A desirable catalytic stability for 50 h was observed. Density functional theory (DFT) calculations indicated excellent activity of the nitrogen-doped Nb(2)CTx was attributed to the introduction of N. This excellent activity was conducive to the adsorption of oxygen and promoted the formation of the OOH intermediate. This work can serve as an important reference for regulating the electronic structure of MXene to expand the application area in the electrochemical field.