Shi Qi, Ji Yongjun, Chen Wenxin, Zhu Yongxia, Li Jing, Liu Hezhi, Li Zhi, Tian Shubo, Wang Ligen, Zhong Ziyi, Wang Limin, Ma Jianmin, Li Yadong, Su Fabing
Gripm Advanced Materials Co., Ltd, Beijing 101407, China.
State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
Natl Sci Rev. 2020 Mar;7(3):600-608. doi: 10.1093/nsr/nwz196. Epub 2019 Nov 28.
Single-atom catalysts are of great interest because they can maximize the atom-utilization efficiency and generate unique catalytic properties; however, much attention has been paid to single-site active components, rarely to catalyst promoters. Promoters can significantly affect the activity and selectivity of a catalyst, even at their low concentrations in catalysts. In this work, we designed and synthesized CuO catalysts with atomically dispersed co-promoters of Sn and Zn. When used as the catalyst in the Rochow reaction for the synthesis of dimethyldichlorosilane, this catalyst exhibited much-enhanced activity, selectivity and stability compared with the conventional CuO catalysts with promoters in the form of nanoparticles. Density functional theory calculations demonstrate that single-atomic Sn substitution in the CuO surface can enrich surface Cu vacancies and promote dispersion of Zn to its atomic levels. Sn and Zn single sites as the co-promoters cooperatively generate electronic interaction with the CuO support, which further facilitates the adsorption of the reactant molecules on the surface, thereby leading to the superior catalytic performance.
单原子催化剂备受关注，因为它们可以使原子利用效率最大化并产生独特的催化性能；然而，人们大多关注单中心活性组分，很少关注催化剂助剂。助剂能显著影响催化剂的活性和选择性，即便其在催化剂中的浓度很低。在这项工作中，我们设计并合成了具有原子级分散的Sn和Zn共助剂的CuO催化剂。当用作合成二甲基二氯硅烷的罗乔反应中的催化剂时，与具有纳米颗粒形式助剂的传统CuO催化剂相比，该催化剂表现出大大增强的活性、选择性和稳定性。密度泛函理论计算表明，CuO表面的单原子Sn取代可富集表面Cu空位并促进Zn分散至原子水平。作为共助剂的Sn和Zn单中心与CuO载体协同产生电子相互作用，这进一步促进了反应物分子在表面的吸附，从而带来优异的催化性能。
