Abstract Single-atom catalyst (SAC) using Au1/Co3O4 has been under investigation experimentally for CO oxidation in recent years. However, the reaction mechanisms for CO oxidation on Au1/Co3O4 are still poorly understood. In this paper, theoretical investigations have been conducted to elucidate the catalytic mechanism of CO oxidation on the Au1/Co3O4 (110) and the pristine Co3O4 (110) by means of the spin-polarized density functional theory puls Hubbard U (DFT + U) calculations, respectively. The calculation results show that 1) the top site of Co3+ (site 1) is the most favorable anchored site for single Au atom on the Co3O4 (110); 2) CO molecule always anchored on the top of the Au atom by a C–Au bond; 3) O2 molecules can be only physisorbed on the single Au atom in whatever way; 4) CO2 molecule can be easily escaped from Au1/Co3O4 (110) at low temperature; 5) the catalytic mechanisms for CO oxidation by extracting the twofold-coordinate oxygen and threefold-coordinate oxygen on the pristine Co3O4 (110) are follow the Mars-van Krevelen mechanism, and the catalytic activity of CO oxidation on the pristine Co3O4 (110) O2f is better than that on O3f; 6) although the pristine Co3O4 (110) has some catalytic activities for CO oxidation, the catalytic activities are far below those of the Au1/Co3O4 (110) via the Eley-Rideal mechanism. In other words, the introducing of single atom Au into the pristine Co3O4 (110) can greatly enhance the catalytic activity of the pristine Co3O4 (110) for CO oxidation. The above results will help in understanding the theoretical mechanisms and the previous experimental results at the molecular lever, and provide a theory base for designing and fabrication of highly active and stable Co3O4 supported SACs.

中文翻译：

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使用密度泛函理论计算在 Au1/Co3O4 (110) 单原子催化剂上 CO 氧化的理论研究

摘要 近年来，人们正在对使用 Au1/Co3O4 的单原子催化剂 (SAC) 进行 CO 氧化的实验研究。然而，Au1/Co3O4 上 CO 氧化的反应机制仍知之甚少。在本文中，通过自旋极化密度泛函理论脉冲 Hubbard U (DFT + U) 进行了理论研究，以阐明 CO 氧化在 Au1/Co3O4 (110) 和原始 Co3O4 (110) 上的催化机制分别计算。计算结果表明：1）Co3+的顶部位点（位点1）是Co3O4（110）上单个Au原子最有利的锚定位点；2）CO分子总是通过C-Au键锚定在Au原子的顶部；3）O2分子只能以任何方式物理吸附在单个Au原子上；4）CO2分子在低温下很容易从Au1/Co3O4（110）中逸出；5）提取原始Co3O4（110）上的双配位氧和三配位氧的CO氧化催化机制遵循Mars-van Krevelen机制，CO氧化对原始Co3O4（110）的催化活性O2f 优于 O3f；6) 尽管原始的 Co3O4 (110) 对 CO 氧化具有一定的催化活性，但通过 Eley-Rideal 机制，催化活性远低于 Au1/Co3O4 (110)。换句话说，将单原子 Au 引入原始 Co3O4（110）可以大大提高原始 Co3O4（110）对 CO 氧化的催化活性。