Wang Lei, Chen Zhiwen, Xiao Yi, Huang Linke, Wang Xiyang, Fruehwald Holly, Akhmetzyanov Dmitry, Hanson Mathew, Chen Zuolong, Chen Ning, Billinghurst Brant, Smith Rodney D L, Singh Chandra Veer, Tan Zhongchao, Wu Yimin A
Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, ON, N2L 3G1, Canada.
Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada.
Nat Commun. 2024 Aug 29;15(1):7477. doi: 10.1038/s41467-024-52004-2.
Achieving large-scale electrochemical CO reduction to multicarbon products with high selectivity using membrane electrode assembly (MEA) electrolyzers in neutral electrolyte is promising for carbon neutrality. However, the unsatisfactory multicarbon products selectivity and unclear reaction mechanisms in an MEA have hindered its further development. Here, we report a strategy that manipulates the interfacial microenvironment of Cu nanoparticles in an MEA to suppress hydrogen evolution reaction and enhance CH conversion. In situ multimodal characterizations consistently reveal well-stabilized Cu-OH species as active sites during MEA testing. The OH radicals generated in situ from water create a locally oxidative microenvironment on the copper surface, stabilizing the Cu species and leading to an irreversible and asynchronous change in morphology and valence, yielding high-curvature nanowhiskers. Consequently, we deliver a selective CH production with a Faradaic efficiency of 55.6% ± 2.8 at 316 mA cm in neutral media.
使用膜电极组件（MEA）电解槽在中性电解质中实现大规模电化学CO还原为多碳产物并具有高选择性，这对碳中和具有重要意义。然而，MEA中多碳产物选择性不理想以及反应机制不明确阻碍了其进一步发展。在此，我们报道了一种策略，即操纵MEA中铜纳米颗粒的界面微环境以抑制析氢反应并增强CH转化。原位多模态表征一致揭示，在MEA测试过程中，稳定的Cu-OH物种作为活性位点。由水原位生成的OH自由基在铜表面形成局部氧化微环境，稳定了Cu物种，并导致形态和价态发生不可逆且不同步的变化，产生高曲率纳米晶须。因此，我们在中性介质中以316 mA cm的电流密度实现了法拉第效率为55.6%±2.8的选择性CH生成。
