Department of Chemical Engineering, Queen's University, Kingston, ON K7L 3N6, Canada.
Chem Soc Rev. 2020 Nov 7;49(21):7488-7504. doi: 10.1039/d0cs00230e. Epub 2020 Oct 5.
Anthropogenic carbon dioxide (CO) emissions contribute to the greenhouse effect and global warming, which can lead to undesirable climate change and extinction of species. Besides the ongoing efforts to develop environmentally benign sources of energy and to advance technologies for the capture and sequestration of CO, the transformation of emitted CO into valuable products is a pragmatic solution to curb its accumulation in the atmosphere. In this regard, electrochemical CO reduction (ECR) powered by renewable electricity provides an attractive approach because it not only converts CO to valuable fuels and chemicals but also offers a solution for the long-term storage of intermittent renewable energies. In ECR, the gas diffusion electrode (GDE) is the most critical component and has been the subject of intensive research in the last few years. This tutorial review provides an insightful guide to developing GDEs with high activity, selectivity, and stability, the three important performance metrics in ECR. First, we introduce critical fundamentals of ECR, including the chemical and physical phenomena at the electrodes as well as the electrochemical cell configurations. Next, we discuss recent advances in GDE design, focusing on their structure-performance correlation and fabrication techniques for each component of GDEs. Finally, we discuss the remaining challenges and propose promising research directions for the design of efficient GDEs. This review aims at promoting the development of industrially relevant ECR systems to bring this technology to practical applications.
人为二氧化碳（CO）排放导致温室效应和全球变暖，可能导致不良的气候变化和物种灭绝。除了正在努力开发环境友好型能源和推进 CO 捕获和封存技术外，将排放的 CO 转化为有价值的产品是抑制其在大气中积累的实用解决方案。在这方面，由可再生电力驱动的电化学 CO 还原（ECR）提供了一种有吸引力的方法，因为它不仅将 CO 转化为有价值的燃料和化学品，而且还为间歇式可再生能源的长期存储提供了一种解决方案。在 ECR 中，气体扩散电极（GDE）是最关键的组件，近年来一直是密集研究的主题。本教程综述提供了一个有见地的指南，用于开发具有高活性、选择性和稳定性的 GDE，这是 ECR 的三个重要性能指标。首先，我们介绍 ECR 的关键基础，包括电极的化学和物理现象以及电化学电池配置。接下来，我们讨论 GDE 设计的最新进展，重点讨论它们的结构-性能相关性以及 GDE 各组件的制造技术。最后，我们讨论了剩余的挑战，并为高效 GDE 的设计提出了有前途的研究方向。本综述旨在促进具有工业相关性的 ECR 系统的发展，将这项技术推向实际应用。
