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-MoTe₂ 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-MoTe₂ 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 (H₂O₂ percentage up to 93%) and decent stability in 0.5 M H₂SO₄. Theoretical simulations evidence that the high activity and selectivity of 2H-MoTe₂ 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.

中文翻译：

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在剥落的碲化钼纳米薄片锯齿形边缘选择性电化学生产过氧化氢

分子氧的双电子还原是实现绿色、温和和按需合成过氧化氢的有效策略。然而，其实际可行性取决于先进电催化剂的开发，优选由非贵重元素组成，以选择性地加速该反应，尤其是在酸性介质中。我们的研究首次介绍了 2H-MoTe ₂作为高效的非贵金属基电催化剂，用于在酸中电化学生产过氧化氢。我们表明剥离的 2H-MoTe ₂纳米薄片具有高活性（起始过电位 ~140 mV 和 27 A g ^-1在 0.4 V 下的大质量活性，相对于可逆氢电极）、高选择性（H ₂ O₂ % 高达 93%）和在 0.5 MH ₂ SO _{4 中的}良好稳定性。理论模拟证明 2H-MoTe ₂的高活性和选择性源于 HOO ^*和 O ^*在其锯齿形边缘的适当结合能，这共同有利于双电子还原而不是分子氧的四电子还原。