Chen Zuolong, Wang Xiyang, Wang Lei, Wu Yimin A
Department of Mechanical and Mechatronics Engineering, Waterloo Institute for Nanotechnology, Materials Interfaces Foundry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Nanoscale. 2022 Aug 11;14(31):11187-11196. doi: 10.1039/d2nr03079a.
Electrochemical CO reduction reactions provide a promising path to effectively convert CO into valuable chemicals and fuels for industries. Among the many CO conversion catalysts, Pd stands out as a promising catalyst for effective CO to CO conversion. Here, using the misfit strain strategy, Ag@Pd bimetallic nanoparticles with different Pd overlayer contents were prepared as CO reduction catalysts. By varying the Pd overlayer content, all the Ag@Pd bimetallic nanoparticles exhibited superior CO conversion performance over their Pd and Ag nanoparticle counterparts. An optimal Pd-to-Ag ratio of 1.5 : 1 yielded the highest CO faradaic efficiency of 94.3% at -0.65 V RHE with a high CO specific current density of 3.9 mA cm. It was found that the Pd content can substantially affect the interplay between the strain effect and ligand effect, resulting in optimized binding properties of the reaction intermediates on the catalyst surface, thereby enhancing the CO reduction performance.
电化学CO还原反应为工业上有效将CO转化为有价值的化学品和燃料提供了一条有前景的途径。在众多CO转化催化剂中，Pd作为一种有望实现高效CO转化的催化剂脱颖而出。在此，采用失配应变策略，制备了具有不同Pd覆盖层含量的Ag@Pd双金属纳米颗粒作为CO还原催化剂。通过改变Pd覆盖层含量，所有Ag@Pd双金属纳米颗粒相对于其Pd和Ag纳米颗粒对应物均表现出优异的CO转化性能。在-0.65 V（相对于可逆氢电极）时，最佳的Pd与Ag比例为1.5∶1，产生了94.3%的最高CO法拉第效率，且具有3.9 mA cm的高CO比电流密度。研究发现，Pd含量可显著影响应变效应和配体效应之间的相互作用，从而优化反应中间体在催化剂表面的结合性能，进而提高CO还原性能。
