MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China.
Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China.
Molecules. 2023 Jun 7;28(12):4606. doi: 10.3390/molecules28124606.
Electrocatalytic reduction of carbon dioxide (CORR) employs electricity to store renewable energy in the form of reduction products. The activity and selectivity of the reaction depend on the inherent properties of electrode materials. Single-atom alloys (SAAs) exhibit high atomic utilization efficiency and unique catalytic activity, making them promising alternatives to precious metal catalysts. In this study, density functional theory (DFT) was employed to predict stability and high catalytic activity of Cu/Zn (101) and Pd/Zn (101) catalysts in the electrochemical environment at the single-atom reaction site. The mechanism of C2 products (glyoxal, acetaldehyde, ethylene, and ethane) produced by electrochemical reduction on the surface was elucidated. The C-C coupling process occurs through the CO dimerization mechanism, and the formation of the *CHOCO intermediate proves beneficial, as it inhibits both HER and CO protonation. Furthermore, the synergistic effect between single atoms and Zn results in a distinct adsorption behavior of intermediates compared to traditional metals, giving SAAs unique selectivity towards the C2 mechanism. At lower voltages, the Zn (101) single-atom alloy demonstrates the most advantageous performance in generating ethane on the surface, while acetaldehyde and ethylene exhibit significant certain potential. These findings establish a theoretical foundation for the design of more efficient and selective carbon dioxide catalysts.
电催化还原二氧化碳（CORR）利用电能将可再生能源以还原产物的形式储存。反应的活性和选择性取决于电极材料的固有性质。单原子合金（SAA）具有高原子利用率和独特的催化活性，是贵金属催化剂的有前途的替代品。在这项研究中，密度泛函理论（DFT）被用于预测电化学环境中单原子反应位点上 Cu/Zn（101）和 Pd/Zn（101）催化剂的稳定性和高催化活性。阐明了电化学还原表面上 C2 产物（乙二醛、乙醛、乙烯和乙烷）生成的机制。C-C 偶联过程通过 CO 二聚化机制发生，*CHOCO 中间体的形成是有益的，因为它抑制了 HER 和 CO 质子化。此外，单原子和 Zn 之间的协同作用导致中间体的吸附行为与传统金属明显不同，使 SAA 对 C2 机制具有独特的选择性。在较低的电压下，Zn（101）单原子合金在表面上生成乙烷的性能最有利，而乙醛和乙烯在一定电位下表现出显著的性能。这些发现为设计更高效和选择性的二氧化碳催化剂奠定了理论基础。
