Atomically Precise Design of PtSn Catalyst for the Understanding of the Role of Sn in Propane Dehydrogenation  

作　　者：Hui Ye Lina Cao Minghui Gu Han Nie Qingqing Gu Bing Yang Yunxing Bai Qinxue Nie Weixin Huang Junling Lu 

机构地区：[1]Institute of Advanced Technology,Key Laboratory of Precision and Intelligent Chemistry,Department of Chemical Physics,Hefei National Research Center for Physical Sciences at the Microscale,Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes,University of Science and Technology of China,Hefei 230026,P.R.China [2]CAS Key Laboratory of Science and Technology on Applied Catalysis,Dalian Institute of Chemical Physics,The Chinese Academy of Sciences,Dalian 116023,P.R.China

出　　处：《Precision Chemistry》2024年第6期245-255,共11页精准化学（英文）

基　　金：supported by the National Natural Science Foundation of China(22102168);the National Science Fund for Distinguished Young Scholars(22025205);the Anhui Natural Science Foundation of China(2108085QB59);Project funded by the China Postdoctoral Science Foundation(BX20190312,2020M671867);the University of Science and Technology of China Youth Innovation Key Fund(YD9990002015);the Fundamental Research Funds for the Central Universities(WK2060000038,WK3430000005);the National Synchrotron Radiation Laboratory(KY2340000135).

摘　　要：Propane dehydrogenation(PDH),an atom-economic reaction to produce high-value-added propylene and hydrogen with high efficiency,has recently attracted extensive attention.The severe deactivation of Pt-based catalysts through sintering and coking remains a major challenge in this high-temperature reaction.The introduction of Sn as a promoter has been widely applied to improve the stability and selectivity of the catalysts.However,the selectivity and stability of PtSn catalysts have been found to vary considerably with synthesis methods,and the role of Sn is still far from fully understanding.To gain in-depth insights into this issue,we synthesized a series of PtSn/SiO_(2)and SnPt/SiO_(2)catalysts by varying the deposition sequence and Pt:Sn ratios using atomic layer deposition with precise control.We found that PtSn/SiO_(2)catalysts fabricated by the deposition of SnO_(x)first and then Pt,exhibited much better propylene selectivity and stability than the SnPt/SiO_(2)catalysts synthesized the other way around.We demonstrate that the presence of Sn species at the Pt-SiO_(2)interface is of essential importance for not only the stabilization of PtSn clusters against sintering under reaction conditions but also the promotion of charge transfers to Pt for high selectivity.Besides the above,the precise regulation of the Sn content is also pivotal for high performance,and the excess amount of Sn might generate additional acidic sites,which could decrease the propylene selectivity and lead to heavy coke formation.These findings provide deep insight into the design of highly selective and stable PDH catalysts.

关 键 词：Propane dehydrogenation PtSn catalysts SINTERING coke formation ACIDITY 

分 类 号：O64[理学—物理化学]