Modification of NiSe2 Nanoparticles by ZIF-8-Derived NC for Boosting H2O2 Production from Electrochemical Oxygen Reduction in Acidic Media

The two-electron oxygen reduction reaction (2e−ORR) has emerged as an attractive alternative for H2O2production. Developing efficient earth-abundant transition metal electrocatalysts and reaction mechanism exploration for H2O2production are important but remain challenging. Herein, a nitrogen-doped carbon-coated NiSe2(NiSe2@NC) electrocatalyst was prepared by successive annealing treatment. Benefiting from the synergistic effect between the NiSe2nanoparticles and NC, the 2e−ORR activity, selectivity, and stability of NiSe2@NC in 0.1 M HClO4was greatly enhanced, with the yield of H2O2being 4.4 times that of the bare NiSe2nanoparticles. The in situ Raman spectra and density functional theory (DFT) calculation revealed that the presence of NC was beneficial for regulating the electronic state of NiSe2and optimizing the adsorption free energy of *OOH, which could enhance the adsorption of O2, stabilize the O-O bond, and boost the production of H2O2. This work provides an effective strategy to improve the performance of the transition metal chalcogenide for 2e−ORR to H2O2.