Electrochemical synthesis of hydrogen peroxide (H₂O₂) through two-electron oxygen reduction represents an attractive alternative for on-site H₂O₂ generation. Here, we develop a facile thermally activated-persulfate approach to obtain oxidized carbon nanotubes (O-CNTs-x, x represents oxidation time) with enhanced H₂O₂ electrosynthesis performance. Electrochemical studies have demonstrated that the optimized O-CNTs-6 (i.e., oxidation time is 6 h) could deliver a sustained high selectivity of around 92% for H₂O₂ over a wide voltage window in 0.1 mol/L KOH and a high H₂O₂ production rate of 296.84 mmol/L g^-1 _cat h^-1. Compared with pristine CNTs, the enhanced catalytic activity primarily stems from the newly-generated oxygen-containing functional groups and some defects created on the surface of O-CNTs-x. Importantly, the proposed oxidation process is proved to be valid for promoting H₂O₂ electrosynthesis performance of the Ketjen black. This study provides an universal oxidation method to obtain highly active carbon-based catalysts and initiates new opportunities for the exploration of high-performance electrosynthesis H₂O₂ catalysts.

通过双电子氧还原电化学合成过氧化氢 (H ₂ O ₂ ) 代表了现场 H ₂ O ₂生成的有吸引力的替代方案。在这里，我们开发了一种简便的热活化过硫酸盐方法来获得具有增强的 H ₂ O ₂电合成性能的氧化碳纳米管（O-CNTs- x，x代表氧化时间）。电化学研究表明，优化的 O-CNTs-6（即氧化时间为 6 小时）可以为 H ₂ O ₂提供约 92% 的持续高选择性在 0.1 mol/L KOH 的宽电压窗口和296.84 mmol/L g ^{- 1} _cat h ^{- 1}的高 H ₂ O ₂生产率。与原始碳纳米管相比，催化活性的增强主要源于新生成的含氧官能团和在 O-CNTs- x表面产生的一些缺陷。重要的是，所提出的氧化过程被证明对于促进科琴黑的H ₂ O ₂电合成性能是有效的。该研究为获得高活性碳基催化剂提供了一种通用的氧化方法，并为探索高性能电合成 H ₂ O ₂催化剂。