Heterostructure and interface engineering of Ni0.85Se-MoSe2@PEI for enhancing electrocatalytic acidic oxygen reduction to hydrogen peroxide

Two-electron oxygen reduction reaction (2e− ORR) for hydrogen peroxide (H2O2) production in acidic solution is becoming a promising synthetic method due to its mild and green process. However, it is still hindered by sluggish kinetics and low selectivity. Given that heterostructure can enhance electron transfer and provide abundant active sites, interface modification can optimize O2 adsorption configurations and the adsorption energy of the reaction intermediates to improve ORR activity and selectivity. Here, we coupled heterostructures of Ni0.85Se-MoSe2 and polyethyleneimine (PEI) functionalization to enhance the activity and selectivity of the 2e− ORR for the efficient production of H2O2 in acidic solutions. The as-fabricated Ni0.85Se-MoSe2@PEI performed 91.7 % selectivity of H2O2 in the rotating ring-disk electrode test, while the H2O2 yield rate was up to 3.57 mol gcat.−1h−1 and the Faraday efficiency was 95.5 % in the H-type cell. In addition, Ni0.85Se-MoSe2@PEI maintains excellent stability in long-term operation, verifying the practicability of the catalyst. The combination of heterostructure and interface engineering provides research ideas for the electrochemical synthesis of H2O2.