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Tan W, Xie S, Cai Y, Wang M, Yu S, Low KB, Li Y, Ma L, Ehrlich SN, Gao F, Dong L, Liu F. Transformation of Highly Stable Pt Single Sites on Defect Engineered Ceria into Robust Pt Clusters for Vehicle Emission Control. Environ Sci Technol 2021; 55:12607-12618. [PMID: 34495644 DOI: 10.1021/acs.est.1c02853] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Engineering surface defects on metal oxide supports could help promote the dispersion of active sites and catalytic performance of supported catalysts. Herein, a strategy of ZrO2 doping was proposed to create rich surface defects on CeO2 (CZO) and, with these defects, to improve Pt dispersion and enhance its affinity as single sites to the CZO support (Pt/CZO). The strongly anchored Pt single sites on CZO support were initially not efficient for catalytic oxidation of CO/C3H6. However, after a simple activation by H2 reduction, the catalytic oxidation performance over Pt/CZO catalyst was significantly boosted and better than Pt/CeO2. Pt/CZO catalyst also exhibited much higher thermal stability. The structural evolution of Pt active sites by H2 treatment was systematically investigated on aged Pt/CZO and Pt/CeO2 catalysts. With H2 reduction, ionic Pt single sites were transformed into active Pt clusters. Much smaller Pt clusters were created on CZO (ca. 1.2 nm) than on CeO2 (ca. 1.8 nm) due to stronger Pt-CeO2 interaction on aged Pt/CZO. Consequently, more exposed active Pt sites were obtained on the smaller clusters surrounded by more oxygen defects and Ce3+ species, which directly translated to the higher catalytic oxidation performance of activated Pt/CZO catalyst in vehicle emission control applications.
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Affiliation(s)
- Wei Tan
- Department of Civil, Environmental, and Construction Engineering, Catalysis Cluster for Renewable Energy and Chemical Transformations (REACT), NanoScience Technology Center (NSTC), University of Central Florida, Orlando, Florida 32816, United States
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Vehicle Emissions Control, School of Environment, Center of Modern Analysis, Nanjing University, Nanjing 210093, P. R. China
| | - Shaohua Xie
- Department of Civil, Environmental, and Construction Engineering, Catalysis Cluster for Renewable Energy and Chemical Transformations (REACT), NanoScience Technology Center (NSTC), University of Central Florida, Orlando, Florida 32816, United States
| | - Yandi Cai
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Vehicle Emissions Control, School of Environment, Center of Modern Analysis, Nanjing University, Nanjing 210093, P. R. China
| | - Meiyu Wang
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, P. R. China
| | - Shuohan Yu
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Vehicle Emissions Control, School of Environment, Center of Modern Analysis, Nanjing University, Nanjing 210093, P. R. China
| | - Ke-Bin Low
- BASF Corporation, Iselin, New Jersey 08830, United States
| | - Yuejin Li
- BASF Corporation, Iselin, New Jersey 08830, United States
| | - Lu Ma
- National Synchrotron Light Source II (NSLS-II), Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Steven N Ehrlich
- National Synchrotron Light Source II (NSLS-II), Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Fei Gao
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Vehicle Emissions Control, School of Environment, Center of Modern Analysis, Nanjing University, Nanjing 210093, P. R. China
| | - Lin Dong
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Vehicle Emissions Control, School of Environment, Center of Modern Analysis, Nanjing University, Nanjing 210093, P. R. China
| | - Fudong Liu
- Department of Civil, Environmental, and Construction Engineering, Catalysis Cluster for Renewable Energy and Chemical Transformations (REACT), NanoScience Technology Center (NSTC), University of Central Florida, Orlando, Florida 32816, United States
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Abstract
In this review, various methods of preparation of activated carbon from agricultural and commercial waste material are reviewed. In addition, we also discuss various activation treatments using a comparative approach. The data are organised in tabulated form for ease of comparative study. A review of numerous characterisation techniques is also provided. The effect of time and temperature, activation conditions, carbonisation conditions and impregnation ratios are explained and several physical and chemical activation treatments of raw materials and their impact on the micro- and mesoporous volumes and surface area are discussed. Lastly, a review of adsorption mechanisms of activated carbon (AC) is also provided.
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Affiliation(s)
- Muhammad Imran Din
- Islamia University of Bahawalpur in 2013, University of the Punjab, Lahore, Pakistan, in November 2009
| | - Sania Ashraf
- Higher Education Department of Punjab Government of Pakistan
| | - Azeem Intisar
- University of the Punjab, Pakistan Pakistan in 2006 and 2009
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