Joyner Nickolas A, Lee Zachary R, Dixon David A
Department of Chemistry and Biochemistry, The University of Alabama, Shelby Hall, Tuscaloosa, Alabama 35487-0336, United States.
J Phys Chem A. 2023 Nov 16;127(45):9541-9549. doi: 10.1021/acs.jpca.3c06389. Epub 2023 Nov 7.
Transition metal oxide (TMO) clusters are being studied for their ability to absorb acid gases generated by energy production processes. The interaction of SO, a byproduct of common industrial processes, with group 4 metal (Ti, Zr, and Hf) oxide nanoclusters, has been predicted using electronic structure methods. The calculations were done at the density functional theory (DFT) and correlated molecular orbital coupled cluster singles and doubles CCSD(T) theory levels. There is a reasonable agreement between the DFT/ωB97x-D energies with the CCSD(T) results. SO is predicted to strongly chemisorb to these clusters, as do NO and CO. For SO, these chemisorption processes favor binding to TMO clusters as SO sulfate in both the terminal and bridging configurations. It is predicted that SO fully extracts the bridging oxygen from the TMO lattice to form bridging SO. This is favorable because of the lower S-O bond dissociation energy of SO, whereas other acid gases add across the bridging oxygen because of their higher A-O bond dissociation energy. SO is capable of physisorption as long as an exposed metal center is present in the lattice. If a metal center has a terminal oxo-group, then SO will prefer the SO configuration. An approximately linear relationship exists between the physisorption energy and proton affinity for rows 2 and 3 elements.
过渡金属氧化物（TMO）团簇因其吸收能源生产过程中产生的酸性气体的能力而受到研究。利用电子结构方法预测了常见工业过程的副产品SO与第4族金属（Ti、Zr和Hf）氧化物纳米团簇之间的相互作用。计算是在密度泛函理论（DFT）以及相关分子轨道耦合簇单双激发（CCSD(T)）理论水平上进行的。DFT/ωB97x-D能量与CCSD(T)结果之间存在合理的一致性。预测SO会像NO和CO一样强烈地化学吸附到这些团簇上。对于SO，这些化学吸附过程有利于以终端和桥连构型的SO硫酸盐形式结合到TMO团簇上。预计SO会从TMO晶格中完全提取桥连氧以形成桥连SO。这是有利的，因为SO的S - O键解离能较低，而其他酸性气体由于其较高的A - O键解离能而在桥连氧上加成。只要晶格中存在暴露的金属中心，SO就能够进行物理吸附。如果金属中心有一个终端氧基团，那么SO将优先选择SO构型。对于第2和第3周期元素，物理吸附能与质子亲和力之间存在近似线性关系。
