Selective electrochemical production of hydrogen peroxide at zigzag edges of exfoliated molybdenum telluride nanoflakes

The two-electron reduction of molecular oxygen represents an effective strategy to enable the green, mild and on-demand synthesis of hydrogen peroxide. Its practical viability, however, hinges on the development of advanced electrocatalysts, preferably composed of non-precious elements, to selectively expedite this reaction, particularly in acidic medium. Our study here introduces 2H-MoTe 2 for the first time as the efficient non-precious-metal-based electrocatalyst for the electrochemical production of hydrogen peroxide in acids. We show that exfoliated 2H-MoTe 2 nanoflakes have high activity (onset overpotential ∼140 mV and large mass activity of 27 A g -1 at 0.4 V versus reversible hydrogen electrode), great selectivity (H 2 O 2 percentage up to 93%) and decent stability in 0.5 M H 2 SO 4 . Theoretical simulations evidence that the high activity and selectivity of 2H-MoTe 2 arise from the proper binding energies of HOO * and O * at its zigzag edges that jointly favor the two-electron reduction instead of the four-electron reduction of molecular oxygen.