Zhou Guangye, Li Boyang, Cheng Guangming, Breckner Christian J, Dean David P, Yang Meiqi, Yao Nan, Miller Jeffrey T, Klok Johannes B M, Tsesmetzis Nicolas, Wang Guofeng, Ren Zhiyong Jason
Department of Civil and Environmental Engineering and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States.
Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
J Am Chem Soc. 2024 Nov 20;146(46):31788-31798. doi: 10.1021/jacs.4c10629. Epub 2024 Nov 6.
The electrocatalytic synthesis of multicarbon products from CO/CO feedstock represents a sustainable method for chemical production with a reduced carbon footprint. Traditional copper catalysts predominantly produce alkenes, but generating valuable and versatile C alcohols, especially high-energy-density C alcohols, has been challenging due to issues with selectivity, activity, and stability. Here, we present the construction of Ru-doped Cu nanowires that enhance the selectivity of -PrOH and C alcohols. In situ Raman spectroscopy shows that our approach promotes both *CO binding and availability, particularly facilitating the formation of high-frequency-bound *CO (*CO) and maintaining multiple *CO adsorption modes on Ru-modified and bare low-coordinated Cu nanowires. Density-functional theory (DFT) simulations illustrate that introducing Ru species onto a low-coordinated Cu step surface simultaneously stabilizes CO and alcohol-related intermediates, shifting the dominant reaction pathway toward alcohols and facilitating CO-C coupling at the expense of ethylene selectivity. In an alkaline gas-diffusion electrolyzer, we attained a maximum Faradaic efficiency (FE) of 35.9% for -PrOH and 62.4% for the total C alcohols. Optimizing parameters in the membrane electrode assembly (MEA) system enabled the one-pot generation and separation of C alcohols, achieving a record concentration of 18.8 wt % (4.2 wt % -PrOH and 14.6 wt % EtOH) with nearly 100% purity at 200 mA/cm over 100 h. This work not only provides new insights and guidance for the development of future catalysts from the perspectives of surface science and mechanisms but also highlights the importance of coupling material engineering with reactor engineering to optimize the production process of high-value alcohol products.
从CO/CO原料电催化合成多碳产物是一种具有减少碳足迹的可持续化学生产方法。传统的铜催化剂主要生成烯烃，但由于选择性、活性和稳定性问题，生成有价值且用途广泛的C醇，尤其是高能量密度的C醇一直具有挑战性。在此，我们展示了Ru掺杂的Cu纳米线的构建，其提高了 -PrOH和C醇的选择性。原位拉曼光谱表明，我们的方法促进了CO的结合和可用性，特别是促进了高频结合的CO（CO）的形成，并在Ru修饰的和裸露的低配位Cu纳米线上保持了多种CO吸附模式。密度泛函理论（DFT）模拟表明，将Ru物种引入低配位的Cu台阶表面同时稳定了CO和与醇相关的中间体，将主要反应途径转向醇，并以乙烯选择性为代价促进了CO-C偶联。在碱性气体扩散电解槽中，我们实现了 -PrOH的最大法拉第效率（FE）为35.9%，总C醇的最大法拉第效率为62.4%。优化膜电极组件（MEA）系统中的参数能够实现C醇的一锅生成和分离，在200 mA/cm²下100小时内实现了创纪录的18.8 wt%的浓度（4.2 wt% -PrOH和14.6 wt% EtOH），纯度接近100%。这项工作不仅从表面科学和机理的角度为未来催化剂的开发提供了新的见解和指导，还强调了将材料工程与反应器工程相结合以优化高价值醇产品生产过程的重要性。
