Silica-modified Pt/TiO2 catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation

doi:10.1016/j.cjche.2024.03.011

中国化学工程学报 ›› 2024, Vol. 70 ›› Issue (6): 189-198.DOI: 10.1016/j.cjche.2024.03.011

Silica-modified Pt/TiO₂ catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation

Zhengjian Hou¹, Yuanyuan Zhu¹, Hua Chi¹, Li Zhao¹, Huijie Wei¹, Yanyan Xi^1,2, Lishuang Ma¹, Xiang Feng^1,3, Xufeng Lin^1,3

1. College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, China;
2. Advanced Chemical Engineering and Energy Materials Research Center, China University of Petroleum (East China), Qingdao 266580, China;
3. State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580, China

收稿日期:2023-12-19 修回日期:2024-03-02 出版日期:2024-06-28 发布日期:2024-08-05
通讯作者: Lishuang Ma,E-mail:hxmals@upc.edu.cn;Xiang Feng,E-mail:xiangfeng@upc.edu.cn;Xufeng Lin,E-mail:hatrick2009@upc.edu.cn
基金资助:
Supports from the National Natural Science Foundation of China (21576291, 22003076), National Natural Science Foundation of China-Outstanding Youth foundation (22322814) and the Fundamental Research Funds for the Central Universities (23CX03007A, 22CX06012A) are gratefully acknowledged.

Silica-modified Pt/TiO₂ catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation

Zhengjian Hou¹, Yuanyuan Zhu¹, Hua Chi¹, Li Zhao¹, Huijie Wei¹, Yanyan Xi^1,2, Lishuang Ma¹, Xiang Feng^1,3, Xufeng Lin^1,3

1. College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, China;
2. Advanced Chemical Engineering and Energy Materials Research Center, China University of Petroleum (East China), Qingdao 266580, China;
3. State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580, China

Received:2023-12-19 Revised:2024-03-02 Online:2024-06-28 Published:2024-08-05
Contact: Lishuang Ma,E-mail:hxmals@upc.edu.cn;Xiang Feng,E-mail:xiangfeng@upc.edu.cn;Xufeng Lin,E-mail:hatrick2009@upc.edu.cn
Supported by:
Supports from the National Natural Science Foundation of China (21576291, 22003076), National Natural Science Foundation of China-Outstanding Youth foundation (22322814) and the Fundamental Research Funds for the Central Universities (23CX03007A, 22CX06012A) are gratefully acknowledged.

摘要/Abstract

摘要： Tuning Strong Metal-support Interactions (SMSI) is a key strategy to obtain highly active catalysts, but conventional methods usually enable TiO encapsulation of noble metal components to minimize the exposure of noble metals. This study demonstrates a catalyst preparation method to modulate a weak encapsulation of Pt metal nanoparticles (NPs) with the supported TiO₂, achieving the moderate suppression of SMSI effects. The introduction of silica inhibits this encapsulation, as reflected in the characterization results such as XPS and HRTEM, while the Ti⁴⁺ to Ti³⁺ conversion due to SMSI can still be found on the support surface. Furthermore, the hydrogenation of cinnamaldehyde (CAL) as a probe reaction revealed that once this encapsulation behavior was suppressed, the adsorption capacity of the catalyst for small molecules like H₂ and CO was enhanced, which thereby improved the catalytic activity and facilitated the hydrogenation of CAL. Meanwhile, the introduction of SiO₂ also changed the surface structure of the catalyst, which inhibited the occurrence of the acetal reaction and improved the conversion efficiency of C=O and C=C hydrogenation. Systematic manipulation of SMSI formation and its consequence on the performance in catalytic hydrogenation reactions are discussed.

关键词: Pt catalyst, Silica modification, Hydrogenation, Cinnamaldehyde, Strong metal-support interaction

Abstract: Tuning Strong Metal-support Interactions (SMSI) is a key strategy to obtain highly active catalysts, but conventional methods usually enable TiO encapsulation of noble metal components to minimize the exposure of noble metals. This study demonstrates a catalyst preparation method to modulate a weak encapsulation of Pt metal nanoparticles (NPs) with the supported TiO₂, achieving the moderate suppression of SMSI effects. The introduction of silica inhibits this encapsulation, as reflected in the characterization results such as XPS and HRTEM, while the Ti⁴⁺ to Ti³⁺ conversion due to SMSI can still be found on the support surface. Furthermore, the hydrogenation of cinnamaldehyde (CAL) as a probe reaction revealed that once this encapsulation behavior was suppressed, the adsorption capacity of the catalyst for small molecules like H₂ and CO was enhanced, which thereby improved the catalytic activity and facilitated the hydrogenation of CAL. Meanwhile, the introduction of SiO₂ also changed the surface structure of the catalyst, which inhibited the occurrence of the acetal reaction and improved the conversion efficiency of C=O and C=C hydrogenation. Systematic manipulation of SMSI formation and its consequence on the performance in catalytic hydrogenation reactions are discussed.

Key words: Pt catalyst, Silica modification, Hydrogenation, Cinnamaldehyde, Strong metal-support interaction

Zhengjian Hou, Yuanyuan Zhu, Hua Chi, Li Zhao, Huijie Wei, Yanyan Xi, Lishuang Ma, Xiang Feng, Xufeng Lin. Silica-modified Pt/TiO₂ catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation[J]. 中国化学工程学报, 2024, 70(6): 189-198.

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Silica-modified Pt/TiO₂ catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation

Silica-modified Pt/TiO₂ catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation

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