Chen Junfeng, Niu Wenzhe, Xue Liangyao, Sun Kai, Yang Xiao, Zhang Xinyue, Li Weihang, Huang Shuanglong, Shi Wenjuan, Zhang Bo
State Key Laboratory of Molecular Engineering of Polymers & Department of Macromolecular Science, Fudan University, Shanghai 200438, China.
Nanoscale. 2024 Sep 12;16(35):16510-16516. doi: 10.1039/d4nr01416b.
The electrochemical reduction of carbon dioxide (CORR) to carbon monoxide represents a cost-effective pathway towards realizing carbon neutrality. To suppress the hydrogen evolution reaction (HER), the presence of alkali cations is critical, which can however lead to precipitate formation on the electrode, adversely impacting the device stability. Employing pure water as the electrolyte in zero-gap CO electrolyzers can address this challenge, albeit at the cost of diminished catalyst performance due to the absence of alkali cations. In this study, we introduce a novel approach by implementing amino modifications on the catalyst surface to mimic the function of alkali metal cations, while simultaneously working in pure water. This modification enhances the adsorption of carbon dioxide and protons, thereby facilitating the CORR while concurrently suppressing the HER. Utilizing this strategy in a zero-gap CO electrolyzer with pure water as the anolyte resulted in an impressive carbon monoxide faradaic efficiency (FE) of 95.5% at a current density of 250 mA cm, while maintaining stability for over 180 hours without any maintenance.
将二氧化碳电化学还原为一氧化碳是实现碳中和的一条经济高效的途径。为了抑制析氢反应（HER），碱金属阳离子的存在至关重要，然而这可能会导致电极上形成沉淀，对器件稳定性产生不利影响。在零间隙CO电解槽中使用纯水作为电解质可以解决这一挑战，尽管由于没有碱金属阳离子，催化剂性能会有所下降。在本研究中，我们引入了一种新方法，即在催化剂表面进行氨基修饰，以模拟碱金属阳离子的功能，同时在纯水中工作。这种修饰增强了二氧化碳和质子的吸附，从而促进了CO2RR，同时抑制了HER。在以纯水为阳极电解液的零间隙CO电解槽中采用该策略，在电流密度为250 mA cm时，一氧化碳法拉第效率（FE）达到了令人印象深刻的95.5%，同时在无需任何维护的情况下保持了超过180小时的稳定性。
