The Electrochemical Energy, Catalysis, and Materials Science Laboratory, Department of Chemistry, Chemical Engineering Division, Technical University Berlin, 10623, Berlin, Germany.
Institute of Chemistry, National Autonomous University of Mexico, 04510, Mexico City, Mexico.
ChemSusChem. 2017 Nov 23;10(22):4642-4649. doi: 10.1002/cssc.201701179. Epub 2017 Aug 21.
A key challenge of the carbon dioxide electroreduction (CO2RR) on Cu-based nanoparticles is its low faradic selectivity toward higher-value products such as ethylene. Here, we demonstrate a facile method for tuning the hydrocarbon selectivities on CuO nanoparticle ensembles by varying the nanoparticle areal density. The sensitive dependence of the experimental ethylene selectivity on catalyst particle areal density is attributed to a diffusional interparticle coupling that controls the de- and re-adsorption of CO and thus the effective coverage of CO intermediates. Thus, higher areal density constitutes dynamically favored conditions for CO re-adsorption and *CO dimerization leading to ethylene formation independent of pH and applied overpotential.
在基于铜的纳米粒子上进行二氧化碳电还原（CO2RR）的一个关键挑战是其对高价值产品（如乙烯）的法拉第选择性较低。在这里，我们通过改变纳米颗粒的面密度展示了一种在氧化铜纳米颗粒集合体上调节烃选择性的简便方法。实验乙烯选择性对催化剂颗粒面密度的敏感依赖性归因于扩散颗粒间耦合，该耦合控制 CO 的脱附和再吸附，从而控制 CO 中间体的有效覆盖率。因此，更高的面密度构成了 CO 再吸附和*CO 二聚化的动态有利条件，从而导致乙烯的形成，与 pH 和施加的过电势无关。
