Ni3B as a highly efficient and selective catalyst for the electrosynthesis of hydrogen peroxide

Electrocatalytic synthesis of hydrogen peroxide (H2O2) via the two-electron oxygen reduction reaction (2e− ORR) is an ideal method for the on-site H2O2 production. Herein, Ni3B is identified as an active, selective, and stable catalyst for ORR to generate H2O2, which exhibits a high selectivity of over 90 % and an onset potential of ∼0.7 V versus the reversible hydrogen electrode (RHE). Furthermore, the mass activity of Ni3B is about 16.5 A g-1 at 0.52 V (RHE), which is comparable to some noble metal alloys. Our experimental results suggest that the high performance of Ni3B originates from the alloying process of Ni and B atoms. The density functional theory calculations reveal that the inner B atoms with high electronegativity decrease the state density of Ni-3d orbital near the Fermi level relative to Ni, which optimizes the binding energy of OOH* and makes Ni3B a highly efficient and stable catalyst for the two-electron ORR.