Shanghai Key Lab of Chemical Assessment and Sustainability, Key Laboratory of Yangtze River Water Environment, School of Chemical Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, 239 Zhangheng Road, Shanghai 200120, China.
Environ Sci Technol. 2023 Nov 7;57(44):17123-17131. doi: 10.1021/acs.est.3c06336. Epub 2023 Oct 24.
Selective production of singlet oxygen (O) as an electrophilic oxidant is crucial for the precise control of chemical targets in environmental fields. Herein, we proposed a strategy to construct a redox interface on electrodes, which can in situ produce inorganic metal hydroperoxides with appropriate oxidative ability during oxygen activation. Benefiting from atomic Cu sites (CuN) in a copper-carbon aerogel electrode, almost complete production of O was achieved, thereby refraining the competitive formation of other reactive oxygen species. The fast electron transfer rate between CuN and electrogenerated HO promoted the in situ formation of copper hydroperoxide (N-Cu-OOH), thereby selectively and efficiently oxidizing intermediate O to O. The optimized production of O was up to 2583 μmol L without additional chemical reagents. We further considered the high production of O for efficiently removing electron-rich organic pollutants from a complex water matrix. Fast kinetics was achieved and considered for removing various pollutants with electron-donating substituents in a nonradical oxidation pathway. The BPA degradation efficiency is less susceptible to the coexisting natural organic matter (NOM) and inorganic ions. Specifically, the kinetic constant for BPA removal is 34 times higher than that for a nanoparticle of a copper-carbon electrode while producing a hydroxyl radical. Our findings highlight the innovative interfacial surface engineering of an electrocatalytic O activation system to selectively generate O for future potential applications.
选择性生成单线态氧 (O) 作为亲电氧化剂对于环境领域中化学靶标的精确控制至关重要。在此，我们提出了一种在电极上构建氧化还原界面的策略，该界面可以在氧气活化过程中就地产生具有适当氧化能力的无机金属过氧化物。得益于铜-碳气凝胶电极中的原子 Cu 位 (CuN)，几乎可以完全生成 O，从而抑制了其他活性氧物种的竞争性形成。CuN 和电生成的 HO 之间的快速电子转移速率促进了铜过氧化物 (N-Cu-OOH) 的原位形成，从而选择性且高效地将中间的 O 氧化为 O。在没有额外化学试剂的情况下，优化后的 O 产量高达 2583 μmol L。我们进一步考虑了高效去除复杂水基质中富电子有机污染物的 O 高产量。在非自由基氧化途径中，通过快速动力学实现并考虑了各种带有供电子取代基的污染物的去除。BPA 的降解效率不易受到共存的天然有机物 (NOM) 和无机离子的影响。具体而言，BPA 去除的动力学常数比生成羟基自由基的铜-碳电极的纳米颗粒高 34 倍。我们的研究结果突出了电催化 O 活化系统的界面表面工程的创新性，以选择性地生成 O，为未来的潜在应用提供了思路。
