Department of Chemistry, The Chinese University of Hong Kong, Hong Kong, China.
School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, China.
Nat Commun. 2023 Apr 5;14(1):1890. doi: 10.1038/s41467-023-37007-9.
Electrochemical water oxidation enables the conversion of HO to HO. It holds distinct advantages to the O reduction reaction, which is restricted by the inefficient mass transfer and limited solubility of O in aqueous media. Nonetheless, most reported anodes suffer from high overpotentials (usually >1000 mV) and low selectivity. Electrolysis at high overpotentials often causes serious decomposition of peroxides and leads to declined selectivity. Herein, we report a ZnGaO anode with dual active sites to improve the selectivity and resist the decomposition of peroxides. Its faradaic efficiency reaches 82% at 2.3 V versus RHE for HO generation through both direct (via OH) and indirect (via HCO) pathways. The percarbonate is the critical species generated through the conversion of bicarbonate at Ga-Ga dual sites. The peroxy bond is stable on the surface of the ZnGaO anode, significantly improving faradaic efficiency.
电化学水氧化能够将 HO 转化为 HO。与 O 还原反应相比，它具有明显的优势，因为 O 在水介质中的传质效率低且溶解度有限。然而，大多数报道的阳极都存在高过电位（通常 >1000 mV）和低选择性的问题。在高过电位下进行电解往往会导致过氧化物严重分解，从而降低选择性。在此，我们报告了一种具有双活性位点的 ZnGaO 阳极，以提高选择性并抵抗过氧化物的分解。通过直接（通过 OH）和间接（通过 HCO）途径，其在相对于 RHE 的 2.3 V 下生成 HO 的法拉第效率达到 82%。过碳酸盐是通过 Ga-Ga 双位点转化碳酸氢盐生成的关键物种。过氧键在 ZnGaO 阳极表面稳定，显著提高了法拉第效率。
