Sun Jikai, Jiang Shuchao, Zhao Yanliang, Wang Honglei, Zhai Dong, Deng Weiqiao, Sun Lei
Institute of Molecular Sciences and Engineering, Institute of Frontier and Interdisciplinary Science, Shandong University, Qingdao 266237, P. R. China.
State Key Laboratory of Molecular Reaction Dynamics, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China.
Phys Chem Chem Phys. 2022 Aug 24;24(33):19938-19947. doi: 10.1039/d2cp02225g.
The hydrogenation of CO into valuable chemical fuels reduces the atmospheric CO content and also has broad economic prospects. Support is essential for catalysts, but many of the reported support materials cannot meet the requirements of accessibility and durability. Herein, we theoretically designed a series of single-atom noble metals anchored on a SiO surface for CO hydrogenation using density functional theory (DFT) calculations. Through theoretical evaluation of the formation energy, hydrogen dissociation capacity, and activity of CO hydrogenation, we found that Ru@SiO is a promising candidate for CO hydrogenation to formic acid. The energy barrier of the rate-determining step of the entire conversion process is 23.9 kcal mol; thus, the reaction can occur under mild conditions. In addition, active and stable origins were revealed through electronic structure analysis. The charge of the metal atom is a good descriptor of the catalytic activity. The Pearson correlation coefficient (PCC) between metal charge and its CO hydrogenation barrier is 0.99. Two solvent models were also used to investigate hydrogen spillover processes and the reaction path was searched by the climbing image nudged-elastic-band (CI-NEB) method. The results indicated that the explicit solvent model could not be simplified into a few solvent molecules, leading to a large difference in the reaction paths. This work will serve as a reference for the future design of more efficient catalysts for CO hydrogenation.
将一氧化碳氢化为有价值的化学燃料既能降低大气中的一氧化碳含量，又具有广阔的经济前景。载体对催化剂至关重要，但许多已报道的载体材料无法满足可及性和耐久性的要求。在此，我们利用密度泛函理论（DFT）计算从理论上设计了一系列锚定在SiO表面的单原子贵金属用于一氧化碳加氢。通过对生成能量、氢解离能力和一氧化碳加氢活性的理论评估，我们发现Ru@SiO是一氧化碳加氢生成甲酸的一个有前景的候选材料。整个转化过程中速率决定步骤的能垒为23.9 kcal mol；因此，该反应可在温和条件下发生。此外，通过电子结构分析揭示了活性和稳定性的根源。金属原子的电荷是催化活性的一个良好描述符。金属电荷与其一氧化碳加氢能垒之间的皮尔逊相关系数（PCC）为0.99。还使用了两种溶剂模型来研究氢溢流过程，并通过爬山图像推挤弹性带（CI-NEB）方法搜索反应路径。结果表明，显式溶剂模型不能简化为几个溶剂分子，导致反应路径存在很大差异。这项工作将为未来设计更高效的一氧化碳加氢催化剂提供参考。
