Bian Lei, Bai Yu, Chen Jia-Yi, Guo Hong-Kai, Liu Shize, Tian Hao, Tian Nana, Wang Zhong-Li
Tianjin Key Laboratory of Applied Catalysis Science & Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
ACS Nano. 2025 Mar 11;19(9):9304-9316. doi: 10.1021/acsnano.5c00696. Epub 2025 Feb 27.
The electrochemical CO reduction reaction (CORR) to produce multicarbon (C) hydrocarbons or oxygenate compounds is a promising route to obtain a renewable fuel or valuable chemicals; however, producing C at high current densities is still a challenge. Herein, we design a hierarchically structured tandem catalysis electrode for greatly improved catalytic activity and selectivity for C products. The tandem catalysis electrode is constructed of a sputtered Ag nanoparticle layer on a hydrophobic polytetrafluoroethylene (PTFE) membrane and a layer of nitrogen-doped carbon (NC)-modified Cu nanowire arrays. The Cu nanowire arrays are grown on PTFE by electrochemical oxidation of sputtered CuAl alloy, in which the chemical etching of metal Al induces the formation of a Cu nanowire array structure. Within hierarchical configuration, CO can be efficiently generated on an active Ag layer and then spillover and transfer to NC-modified Cu nanowire array layer, in which Cu/NC interfaces can enhance *CO trapping and adsorption. During the CORR, the optimized tandem catalysis electrode achieves superior Faradaic efficiencies of 53.5% and 87.5% for ethylene (CH) and C products at the current density of 519.0 mA cm, respectively, with a high C/C ratio of 10.42 and long-term stability up to 50 h. Raman and attenuated total reflection-surface enhanced infrared absorption spectroscopy (ATR-SEIRAS) confirm that the Ag-Cu-NC tandem catalysis system significantly enhances the linear adsorption of *CO intermediates and the dissociation of HO, improves the C-C coupling capability, and stabilizes the key intermediate *OCCOH to produce C products.
通过电化学一氧化碳还原反应（CORR）制备多碳（C）烃类或含氧化合物是获取可再生燃料或有价值化学品的一条有前景的途径；然而，在高电流密度下生成碳仍然是一项挑战。在此，我们设计了一种具有分级结构的串联催化电极，以大幅提高对碳产物的催化活性和选择性。该串联催化电极由疏水性聚四氟乙烯（PTFE）膜上的溅射银纳米颗粒层以及一层氮掺杂碳（NC）修饰的铜纳米线阵列构成。铜纳米线阵列通过对溅射的CuAl合金进行电化学氧化在PTFE上生长，其中金属铝的化学蚀刻诱导形成铜纳米线阵列结构。在分级结构中，一氧化碳能够在活性银层上高效生成，然后溢出并转移至NC修饰的铜纳米线阵列层，在该层中铜/NC界面能够增强CO的捕获和吸附。在CORR过程中，优化后的串联催化电极在519.0 mA cm的电流密度下，对乙烯（CH）和碳产物的法拉第效率分别达到了优异的53.5%和87.5%，具有10.42的高碳/碳比以及长达50小时的长期稳定性。拉曼光谱和衰减全反射 - 表面增强红外吸收光谱（ATR - SEIRAS）证实，Ag - Cu - NC串联催化体系显著增强了CO中间体的线性吸附和H₂O的解离，提高了C - C偶联能力，并稳定了关键中间体*OCCOH以生成碳产物。
