浙江大学吴浩斌团队报道了脉冲诱导阴离子富集定制CO₂电还原。相关研究成果于2023年11月9日发表于国际一流学术期刊《美国化学会杂志》。

将二氧化碳电化学转化为特定的高价值产品对于碳中和的经济至关重要。然而，在铜基催化剂上控制CO₂电还原的产物分布仍然具有挑战性。

该文中，研究人员提出了一种阴离子富集策略，以通过脉冲电解策略有效地确定*CO还原的路线。在阴极上周期性地施加正电位时，电极附近的阴离子浓度明显增加。通过采用KF、KCl和KHCO₃作为电解质，在脉冲电解下，商业铜箔上的主要CO₂电还原产物可以调节为CO（53%±2.5）、C2+（76.6±2.1%）和CH4（42.6±2.1%）。值得注意的是，可以通过简单地改变电解质的组成来精细地调整CO/CH4、CH4/C2+和C2+/CO的比率。

密度泛函理论计算表明，局部富集的阴离子由于其特定的电负性和体积，可以以不同的方式影响关键的CO₂RR中间体，这导致了不同的选择性。

该研究强调了在电极-电解质界面调节离子物种对于定制CO₂电还原产品的重要性。

附：英文原文

Title: Customizing CO2 Electroreduction by Pulse-Induced Anion Enrichment

Author: Jianghao Wang, Yanyang Qin, Shoutong Jin, Yue Yang, Jie Zhu, Xiaotong Li, Xiangzhou Lv, Jie Fu, Zijian Hong, Yaqiong Su, Hao Bin Wu

Issue&Volume: November 9, 2023

Abstract: Electrochemically converting CO2 into specified high-value products is critical for carbon neutral economics. However, governing the product distribution of the CO2 electroreduction on Cu-based catalysts remains challenging. Herein, we put forward an anion enrichment strategy to efficiently dictate the route of *CO reduction by a pulsed electrolysis strategy. Upon periodically applying a positive potential on the cathode, the anion concentration in the vicinity of the electrode increases apparently. By adopting KF, KCl, and KHCO3 as electrolytes, the dominant CO2 electroreduction product on commercial Cu foil can be tuned into CO (53% ± 2.5), C2+ (76.6 ± 2.1%), and CH4 (42.6 ± 2.1%) under pulsed electrolysis. Notably, one can delicately tailor the ratios of CO/CH4, CH4/C2+, and C2+/CO by simply changing the composition of the electrolyte. Density functional theory calculations demonstrate that locally enriched anions can affect the key CO2RR intermediates in different ways owing to their specific electronegativity and volume, which leads to the distinct selectivity. The present study highlights the importance of tuning ionic species at the electrode–electrolyte interface for customizing the CO2 electroreduction products.

DOI: 10.1021/jacs.3c08748

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.3c08748