Liu Shenning, Wang Yuxian, Liu Ya, Chen Peihan, Kong Tao, Duan Xiaoguang, Chen Chunmao, Sun Hongqi, Wang Shaobin
State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing, China.
School of Chemical Engineering, The University of Adelaide, Adelaide, SA, Australia.
Nat Commun. 2025 Jul 1;16(1):5921. doi: 10.1038/s41467-025-61181-7.
Cobalt-containing spinel oxides are promising platforms to fine-tune the intrinsic activity/selectivity of their geometric sites in catalysis. However, the role of tetrahedrally occupied Co (Co) and Co in an octahedral site (Co) in controlling the catalytic activity remains controversial. Herein, we investigated a geometrical-site-dependent catalytic activation of ozone respectively on the Co and Co sites. The same exposure of [111] crystal facet is achieved by substituting those undesired sites with catalytically inactive cations. The highly spin-polarized Co sites invoke strong orbital interactions and intensive electron transfer with the adsorbed O and become the active sites for selectively producing surface-bound hydroxyl radicals (OH) and avoiding the formation of unfavorable singlet oxygen (O), resulting in a 17.6-fold increase in turnover frequency (TOF). This work enlightens the spin-polarized electronic states into regulating the reaction thermodynamics in transition metal oxide-induced catalysis and envisages the practical application potentials of geometric site engineered spinel oxides.
含钴尖晶石氧化物是在催化中微调其几何位点本征活性/选择性的有前景的平台。然而，四面体配位的钴（Co）和八面体位点中的钴（Co）在控制催化活性方面的作用仍存在争议。在此，我们分别研究了臭氧在Co和Co位点上的几何位点依赖性催化活化。通过用催化惰性阳离子取代那些不需要的位点，实现了[111]晶面的相同暴露。高度自旋极化的Co位点引发与吸附的O的强轨道相互作用和强烈的电子转移，并成为选择性产生表面结合羟基自由基（OH）并避免形成不利的单线态氧（O）的活性位点，导致周转频率（TOF）增加17.6倍。这项工作将自旋极化电子态引入到过渡金属氧化物诱导催化中调节反应热力学，并设想了几何位点工程化尖晶石氧化物的实际应用潜力。
