Zhang Ting, Zhou Jinlei, Luo Ting, Lu Ji-Qing, Li Zhengquan, Weng Xuexiang, Yang Fa
Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China.
Chemistry. 2023 Aug 15;29(46):e202301455. doi: 10.1002/chem.202301455. Epub 2023 Jul 19.
Electrochemical CO reduction reaction (CO RR) provides a promising approach for sustainable chemical fuel production of carbon neutrality. Neutral and alkaline electrolytes are predominantly employed in the current electrolysis system, but with striking drawbacks of (bi)carbonate (CO /HCO ) formation and crossover due to the rapid and thermodynamically favourable reaction between hydroxide (OH ) with CO , resulting in low carbon utilization efficiency and short-lived catalysis. Very recently, CO RR in acidic media can effectively address the (bi)carbonate issue; however, the competing hydrogen evolution reaction (HER) is more kinetically favourable in acidic electrolytes, which dramatically reduces CO conversion efficiency. Thus, it is a big challenge to effectively suppress HER and accelerate acidic CO RR. In this review, we begin by summarizing the recent progress of acidic CO electrolysis, discussing the key factors limiting the application of acidic electrolytes. We then systematically discuss addressing strategies for acidic CO electrolysis, including electrolyte microenvironment modulation, alkali cations adjusting, surface/interface functionalization, nanoconfinement structural design, and novel electrolyzer exploitation. Finally, the new challenges and perspectives of acidic CO electrolysis are suggested. We believe this timely review can arouse researchers' attention to CO crossover, inspire new insights to solve the "alkalinity problem" and enable CO RR as a more sustainable technology.
电化学一氧化碳还原反应（CO RR）为可持续生产碳中和化学燃料提供了一种很有前景的方法。目前的电解系统主要采用中性和碱性电解质，但存在显著缺点，即由于氢氧根（OH⁻）与一氧化碳之间快速且热力学有利的反应，会形成（碳酸氢根）（CO₃²⁻/HCO₃⁻）并发生交叉，导致碳利用效率低和催化寿命短。最近，酸性介质中的CO RR可以有效解决（碳酸氢根）问题；然而，在酸性电解质中，竞争性析氢反应（HER）在动力学上更有利，这大大降低了CO转化效率。因此，有效抑制HER并加速酸性CO RR是一项巨大挑战。在这篇综述中，我们首先总结了酸性CO电解的最新进展，讨论了限制酸性电解质应用的关键因素。然后，我们系统地讨论了酸性CO电解的应对策略，包括电解质微环境调控、碱金属阳离子调节、表面/界面功能化、纳米限域结构设计和新型电解槽开发。最后，提出了酸性CO电解的新挑战和展望。我们相信，这篇及时的综述能够引起研究人员对CO交叉问题的关注，激发解决“碱度问题”的新见解，并使CO RR成为一种更可持续的技术。
