Wang Fangjun, Chen Shiyi, Xu Xiang, Chen Xiaohan, Wu Jiang, Chen Shubo, Xiang Wenguo, Duan Lunbo
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China.
Institute of Engineering, Thermophysics, Chinese Academy of Science, Beijing, 100029, China.
Small. 2025 Sep;21(35):e2505474. doi: 10.1002/smll.202505474. Epub 2025 Jul 17.
In recent years, single-atom catalysts (SACs) have emerged as a prominent research focus in electrochemical CO reduction reactions (CORR), owing to their exceptional atomic utilization efficiency and superior catalytic performance. Nevertheless, their practical implementation may be constrained by inherently low metal loading and the presence of linear relationships imposed by their structurally simplistic active sites. Atomic-level engineering of active sites represents a transformative strategy to overcome the intrinsic limitations of SACs. Building upon the foundation of SACs, dual-atom catalysts (DACs) exhibit enhanced metal loading capacity and more sophisticated active site configurations, leading to superior catalytic performance and broader opportunities in electrocatalytic applications. This review first explains the possible reaction pathways for product generation via CORR, including the underlying mechanisms, key intermediates, and strategies to optimize these pathways. Subsequently, a comprehensive overview of synthetic strategies and precise atomic-level characterization of atomic-scale catalysts is presented. SACs and DACs are systematically categorized according to their active site architectures and electronic configurations. The significant advantages of DACs over SACs in increasing the metal atom loading, promoting the adsorption and activation of CO molecules, regulating intermediates, and promoting C-C coupling are compared. Finally, the prevailing challenges and future development prospects of DACs are summarized.
近年来,单原子催化剂(SACs)因其卓越的原子利用效率和优异的催化性能,已成为电化学CO还原反应(CORR)领域的一个突出研究重点。然而,其实际应用可能会受到固有低金属负载量以及结构简单的活性位点所带来的线性关系的限制。活性位点的原子级工程是克服SACs固有局限性的一种变革性策略。在SACs的基础上,双原子催化剂(DACs)展现出更高的金属负载能力和更复杂的活性位点构型,从而在电催化应用中具有更优异的催化性能和更广阔的机遇。本综述首先解释了通过CORR生成产物的可能反应途径,包括潜在机制、关键中间体以及优化这些途径的策略。随后,对原子尺度催化剂的合成策略和精确原子级表征进行了全面概述。SACs和DACs根据其活性位点结构和电子构型进行了系统分类。比较了DACs相较于SACs在增加金属原子负载量、促进CO分子的吸附和活化、调节中间体以及促进C-C偶联方面的显著优势。最后,总结了DACs目前面临挑战和未来发展前景。