Origin of synergistic effects in bicomponent cobalt oxide-platinum catalysts for selective hydrogenation reaction
Origin of synergistic effects in bicomponent cobalt oxide-platinum catalysts for selective hydrogenation reaction
复制标题
双组分氧化钴-铂催化剂选择性加氢协同效应的起源
DOI：
10.1038/s41467-019-11970-8
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发表时间：
2019
影响因子：
16.6
通讯作者：
Qin Yong
中科院分区：
文献类型：
--
作者：
Zhang Jiankang;Gao Zhe;Wang Sen;Wang Guofu;Gao Xiaofeng;Zhang Baiyan;Xing Shuangfeng;Zhao Shichao;Qin Yong
双组分催化剂的协同性质仍然是一个具有挑战性的问题，由于难以构建明确的催化体系。本文通过原子层沉积（ALD）法设计了一系列紧密接触的CoOxPt/TiO 2和空间分离的CoOx/TiO 2/Pt催化剂，研究了CoOx-Pt催化剂选择加氢协同效应的起源。对于CoOx/TiO 2/Pt，CoOx和Pt被二氧化钛纳米管的壁隔开，并且CoOx-Pt亲密度可以精确地调节。与CoOxPt/TiO 2一样，CoOxPt/TiO 2/Pt催化剂对肉桂醇的选择性高于单组分TiO 2/Pt催化剂，表明CoOx-Pt纳米尺度的紧密性对肉桂醇的选择性几乎没有影响。提高的选择性归因于由促进的氢溢出导致的氧空位增加。此外，铂-氧空位界面位置被确定为活性位点，通过ALD选择性地覆盖CoOxor铂。我们的研究为理解双组分和双功能催化剂的协同性质提供了指导。
The synergistic nature of bicomponent catalysts remains a challenging issue, due to the difficulty in constructing well-defined catalytic systems. Here we study the origin of synergistic effects in CoOx-Pt catalysts for selective hydrogenation by designing a series of closely contacted CoOxPt/TiO2and spatially separated CoOx/TiO2/Pt catalysts by atomic layer deposition (ALD). For CoOx/TiO2/Pt, CoOxand platinum are separated by the walls of titania nanotubes, and the CoOx-Pt intimacy can be precisely tuned. Like CoOxPt/TiO2, the CoOx/TiO2/Pt shows higher selectivity to cinnamyl alcohol than monometallic TiO2/Pt, indicating that the CoOx-Pt nanoscale intimacy almost has no influence on the selectivity. The enhanced selectivity is ascribed to the increased oxygen vacancy resulting from the promoted hydrogen spillover. Moreover, platinum-oxygen vacancy interfacial sites are identified as the active sites by selectively covering CoOxor platinum by ALD. Our study provides a guide for the understanding of synergistic nature in bicomponent and bifunctional catalysts.