Du Ruian, Li Tan, Wu Qiqi, Wang Peng, Yang Xianfeng, Fan Yan, Qiu Yongcai, Yan Keyou, Wang Pei, Zhao Yun, Zhao Wei-Wei, Chen Guangxu
School of Environment and Energy, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou 510006, China.
Analytical and Testing Centre, South China University of Technology, Guangzhou 510640, China.
ACS Appl Mater Interfaces. 2022 Aug 17;14(32):36527-36535. doi: 10.1021/acsami.2c05992. Epub 2022 Aug 4.
The Cu/Cu interface in the Cu-based electrocatalyst is essential to promote the electrochemical reduction of carbon dioxide (ERCO) to produce multi-carbon hydrocarbons and alcohols with high selectivity. However, due to the high activity of the Cu/Cu interface, it is easy to be oxidized in the air. How to control and prepare a Cu-based electrocatalyst with an abundant and stable Cu/Cu interface in situ is a huge challenge. Here, combined with density functional theory (DFT) calculations and experimental studies, we found that the trace halide ions adsorbed on CuO can slow the reduction kinetics of Cu → Cu, which allowed us to in-situ well control the synthesis of the CuO-derived electrocatalyst with rich Cu/Cu interfaces. Our Cu catalyst with a rich Cu/Cu interface exhibits excellent ERCO performance. Under the operation potential of -0.98 V versus RHE, the Faraday efficiency of CH and C products are 55.8 and 75.7%, respectively, which is about 16% higher than that of CuO-derived electrocatalysts that do not use halide ions. The high comes from the improvement of the coupling efficiency of reaction intermediates such as CO-CO, which is proved by DFT calculations, and the suppression of hydrogen evolution reaction. Therefore, we provide an in-situ engineering strategy, which is simple and effective for the design and preparation of high-performance ERCO catalysts.
铜基电催化剂中的Cu/Cu界面对于促进二氧化碳电化学还原（ERCO）以高选择性地生成多碳烃类和醇类至关重要。然而，由于Cu/Cu界面的高活性，其在空气中容易被氧化。如何原位控制并制备具有丰富且稳定的Cu/Cu界面的铜基电催化剂是一项巨大的挑战。在此，结合密度泛函理论（DFT）计算和实验研究，我们发现吸附在CuO上的痕量卤离子能够减缓Cu→Cu的还原动力学，这使我们能够原位良好地控制富含Cu/Cu界面的CuO衍生电催化剂的合成。我们具有丰富Cu/Cu界面的铜催化剂展现出优异的ERCO性能。在相对于可逆氢电极（RHE）为-0.98 V的操作电位下，CH和C产物的法拉第效率分别为55.8%和75.7%，这比未使用卤离子的CuO衍生电催化剂高出约16%。高法拉第效率源于诸如CO-CO等反应中间体耦合效率的提高，这由DFT计算所证实，以及析氢反应的抑制。因此，我们提供了一种原位工程策略，该策略对于高性能ERCO催化剂的设计和制备简单且有效。
