Chen Jiao-Jiao, Wang Si-Dun, Ding Xun-Lei, He Sheng-Gui
School of Mathematics and Physics, North China Electric Power University, Beinong Road 2, Changping, Beijing 102206, China.
Institute of Clusters and Low Dimensional Nanomaterials, North China Electric Power University, Beinong Road 2, Changping, Beijing 102206, China.
J Phys Chem Lett. 2024 Sep 5;15(35):9078-9083. doi: 10.1021/acs.jpclett.4c02045. Epub 2024 Aug 28.
Water (HO) is ubiquitous in the environment and inevitably participates in many surface reactions, including CO oxidation. Acquiring a fundamental understanding of the roles of HO molecules in CO oxidation poses a challenging but pivotal task in real-life catalysis. Herein, benefiting from state-of-the-art mass-spectrometric experiments and quantum chemical calculations, we identified that the dissociation of a HO molecule on each of the cerium oxide cluster anions (CeO)O ( = 1-4) at room temperature can create a new atomic oxygen radical (O) that then oxidizes a CO molecule. The size-dependent reactivity of HO-mediated CO oxidation on (CeO)O clusters was rationalized by the orbital compositions (O) and energies of the lowest unoccupied molecular orbitals of active O radicals modified by HO dissociation. Our findings not only provide new insights into HO-mediated CO oxidation but also demonstrate the importance of HO in modulating the reactivity of the O radicals.
水（H₂O）在环境中无处不在，不可避免地参与许多表面反应，包括一氧化碳（CO）氧化反应。深入了解H₂O分子在CO氧化反应中的作用，在实际催化过程中是一项具有挑战性但至关重要的任务。在此，借助最先进的质谱实验和量子化学计算，我们发现室温下H₂O分子在每个氧化铈簇阴离子（CeOₓ）ₙ⁻（x = 1 - 4）上的解离会产生一个新的原子氧自由基（O），然后该自由基会氧化一个CO分子。通过H₂O解离修饰的活性O自由基的最低未占据分子轨道的轨道组成（O）和能量，解释了（CeOₓ）ₙ⁻簇上H₂O介导的CO氧化反应的尺寸依赖性反应活性。我们的研究结果不仅为H₂O介导的CO氧化反应提供了新的见解，还证明了H₂O在调节O自由基反应活性方面的重要性。
