CMA Key Open Laboratory of Transforming Climate Resources to Economy
Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China
College of Environment, Zhejiang University of Technology
School of Environmental Science and Engineering, Southwest Jiaotong University

基于可再生能源的电催化二氧化碳还原反应(eCO2RR)可以将CO2转化为高附加值的化学品和燃料,是应对大气CO2浓度急剧升高和全球变暖的一种可行方案。然而,在传统的中性或碱性电解液中,eCO2RR存在严重的碳损失问题,导致CO2的理论单程碳转化率(SPCE)低于50%,同时电解液的再生需要消耗额外能源。相比之下,酸性电解液可以有效解决碳损失问题,其理论SPCE可达100%,备受研究者关注。目前大多数研究仍集中在催化剂的优化上,而对气体扩散电极(GDE)、电解质和质子膜等固液气界面的优化关注不足,这些因素均会影响eCO2RR的选择性、稳定性和能量效率。通过系统优化酸性eCO2RR三相界面(固相、液相、气相),在100mA·cm−2电流密度和低于5V的槽压下,实现了法拉第效率(FECO)超过90%,并且稳定运行110h。最后,将电极面积放大至100cm2,初步研究了工艺放大的影响机制,并提出了一种新的间歇运行策略。针对酸性eCO2RR的界面优化和工艺放大研究有望为其工业化应用提供理论支持。

The electrocatalytic carbon dioxide reduction reaction (eCORR) powered by renewableenergy can convert CO into high-value chemicals and fuels. It is a viable solution to address the sharpincrease in atmospheric CO concentration and global warming. However, in traditional neutral orEnergy Environmental Protectionalkaline electrolytes, eCORR suffers from severe carbon loss, resulting in a theoretical single-passcarbon conversion efficiency (SPCE) of less than 50%, and the regeneration of the electrolyte requiresadditional energy. Acidic electrolytes can effectively solve the carbon loss issue, achieving a theoreticalSPCE of 100%, which has attracted widespread attention worldwide. Nevertheless, most previousstudies focused on catalyst optimization, with insufficient emphasis on optimizing solid-liquid-gasinterfaces such as gas diffusion electrodes (GDEs), electrolytes, and proton membranes. These factorsinfluence the selectivity, stability, and energy efficiency of eCORR. In this study, we systematicallyoptimized the three-phase interface (solid, liquid, and gas) of the acidic eCORR, achieving a faradaicefficiency for CO (FE) of over 90% at a current density of 100 mA·cm and a cell voltage of lessthan 5 V, with stable operation for 110 hours. Finally, we scaled up the electrode area to 100 cm,exploring the impact mechanism of process scale-up, and proposing a new intermittent operationstrategy. This research on interface optimization and process scale-up of acidic eCORR is expected toprovide a theoretical foundation for its potential industrial applications.

中国气象局气候资源经济转化重点开放实验室开放课题(2024004K);浙江省自然科学基金资助项目(LQ24B070010);湖州市自然科学资金资助项目(2022YZ22)

马飞余,卢先龙,赵学洋,等.酸性流动电解槽中电催化还原CO2制CO的界面优化及工艺放大研究[J].能源环境保护,2024,38(6):151−159.

MA Feiyu, LU Xianlong , ZHAO Xueyang , et al. Interface optimization and process scale -up study ofelectrocatalytic reduction of CO2 to CO in acidic flow electrolyzers[J]. Energy Environmental Protection,2024, 38(6): 151−159.