Porous Nitrogen-doped Nb2C Nanosheets for Electrocatalytic ORR to Selectively Produce H2O2.

Abstract

The two-electron pathway in the oxygen reduction reaction (ORR) represents an efficient and environmentally friendly approach for H2O2 production. Among various types of potential catalysts, MXene have garnered significant attention due to their outstanding electrical conductivity, abundant edge active sites, and low costs. In this study, we successfully synthesize porous N-doped Nb2C nanosheets (N-Nb2C) via a room-temperature ammonia etching method and investigate their ORR performance toward the formation of H2O2. The doping of nitrogen effectively modulates the electronic structure of Nb2C nanosheets, while the abundant surface pores formed during ammonia etching facilitate the ORR process. Hence, the electrocatalytic performance of N-Nb2C nanosheets is significantly improved, demonstrating excellent long-term stability and durability. Notably, in rotating ring-disk electrode (RRDE) tests, the N-Nb2C catalyst achieves a remarkable H2O2 yield of 86.8%, highlighting its potential for selective H2O2 production through electrocatalytic ORR. Our findings suggest that N-doped Nb2C holds great promise for applications in two-electron oxygen reduction for H2O2 synthesis.