Wu Minfang, Zhu Chang, Wang Kang, Li Guihua, Dong Xiao, Song Yanfang, Xue Jiamin, Chen Wei, Wei Wei, Sun Yuhan
CAS Key Laboratory of Low-Carbon Conversion Science and Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China.
University of the Chinese Academy of Sciences, Beijing 100049, China.
ACS Appl Mater Interfaces. 2020 Mar 11;12(10):11562-11569. doi: 10.1021/acsami.9b21153. Epub 2020 Mar 2.
The electrochemical conversion of carbon dioxide (CO) to fuels and chemicals is an opportunity for sustainable energy research that can realize both renewable energy storage and negative carbon cycle feedback. However, the selective generation of multicarbon products is challenging because of the competitive hydrogen evolution reaction (HER) and protonation of the reacting adsorbate. Copper-based materials have been the most commonly studied catalysts for CO electroreduction due to their ability to produce a substantial amount of C products. Here, we report that a nanodendrite configuration can improve the electrocatalytic performance of Cu catalysts, especially multicarbon product formation, while suppressing HER and methane production. The abundant conductive networks derived from the fractal copper dendritic structures with a high electrochemically active surface area (ECSA) facilitate electron transport and mass transfer, leading to superior kinetics for the formation of multicarbon products from CO electroreduction. As a result, approximately 70-120% higher ethylene and 60-220% higher C (-PrOH and propanal) yields with lower onset potentials were produced over Cu nanodendrites compared to the initial Cu particles. This work opens an avenue for promoting CO electrochemical reduction to multicarbon products by catalyst configuration modulation.
将二氧化碳（CO₂）电化学转化为燃料和化学品是可持续能源研究的一个契机，有望实现可再生能源存储和负碳循环反馈。然而，由于存在竞争性析氢反应（HER）以及反应吸附物的质子化作用，选择性生成多碳产物具有挑战性。铜基材料因其能够大量生成含碳产物，一直是CO₂电还原研究中最常用的催化剂。在此，我们报道一种纳米枝晶结构能够提高铜催化剂的电催化性能，特别是多碳产物的生成，同时抑制HER和甲烷生成。源自具有高电化学活性表面积（ECSA）的分形铜树枝状结构的丰富导电网络，促进了电子传输和传质，从而使CO₂电还原生成多碳产物的动力学更优。结果，与初始铜颗粒相比，Cu纳米枝晶产生的乙烯产率提高了约70 - 120%，C₃产物（-PrOH和丙醛）产率提高了60 - 220%，且起始电位更低。这项工作为通过催化剂结构调控促进CO₂电化学还原为多碳产物开辟了一条途径。
