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A Brief Overview of Recent Progress in Porous Silica as Catalyst Supports. JOURNAL OF COMPOSITES SCIENCE 2021. [DOI: 10.3390/jcs5030075] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Porous silica particles have shown applications in various technological fields including their use as catalyst supports in heterogeneous catalysis. The mesoporous silica particles have ordered porosity, high surface area, and good chemical stability. These interesting structural or textural properties make porous silica an attractive material for use as catalyst supports in various heterogeneous catalysis reactions. The colloidal nature of the porous silica particles is highly useful in catalytic applications as it guarantees better mass transfer properties and uniform distribution of the various metal or metal oxide nanocatalysts in solution. The catalysts show high activity, low degree of metal leaching, and ease in recycling when supported or immobilized on porous silica-based materials. In this overview, we have pointed out the importance of porous silica as catalyst supports. A variety of chemical reactions catalyzed by different catalysts loaded or embedded in porous silica supports are studied. The latest reports from the literature about the use of porous silica-based materials as catalyst supports are listed and analyzed. The new and continued trends are discussed with examples.
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Infantes-Molina A, Villanova A, Talon A, Kohan MG, Gradone A, Mazzaro R, Morandi V, Vomiero A, Moretti E. Au-Decorated Ce-Ti Mixed Oxides for Efficient CO Preferential Photooxidation. ACS APPLIED MATERIALS & INTERFACES 2020; 12:38019-38030. [PMID: 32687700 PMCID: PMC7458359 DOI: 10.1021/acsami.0c08258] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/20/2020] [Indexed: 06/11/2023]
Abstract
We investigated the photocatalytic behavior of gold nanoparticles supported on CeO2-TiO2 nanostructured matrixes in the CO preferential oxidation in H2-rich stream (photo-CO-PROX), by modifying the electronic band structure of ceria through addition of titania and making it more suitable for interacting with free electrons excited in gold nanoparticles through surface plasmon resonance. CeO2 samples with different TiO2 concentrations (0-20 wt %) were prepared through a slow coprecipitation method in alkaline conditions. The synthetic route is surfactant-free and environmentally friendly. Au nanoparticles (<1.0 wt % loading) were deposited on the surface of the CeO2-TiO2 oxides by deposition-precipitation. A benchmarking sample was also considered, prepared by standard fast coprecipitation, to assess how a peculiar morphology can affect the photocatalytic behavior. The samples appeared organized in a hierarchical needle-like structure, with different morphologies depending on the Ti content and preparation method, with homogeneously distributed Au nanoparticles decorating the Ce-Ti mixed oxides. The morphology influences the preferential photooxidation of CO to CO2 in excess of H2 under simulated solar light irradiation at room temperature and atmospheric pressure. The Au/CeO2-TiO2 systems exhibit much higher activity compared to a benchmark sample with a non-organized structure. The most efficient sample exhibited CO conversions of 52.9 and 80.2%, and CO2 selectivities equal to 95.3 and 59.4%, in the dark and under simulated sunlight, respectively. A clear morphology-functionality correlation was found in our systematic analysis, with CO conversion maximized for a TiO2 content equal to 15 wt %. The outcomes of this study are significant advancements toward the development of an effective strategy for exploitation of hydrogen as a viable clean fuel in stationary, automotive, and portable power generators.
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Affiliation(s)
- Antonia Infantes-Molina
- Departamento
de Química Inorgánica, Cristalografía y Mineralogía
(Unidad Asociada al ICP-CSIC), Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos, 29071 Málaga, Spain
| | - Andrea Villanova
- Department
of Molecular Sciences and Nanosystems, Ca’
Foscari University of Venice, Via Torino 155, 30172 Mestre Venezia, Italy
| | - Aldo Talon
- Department
of Molecular Sciences and Nanosystems, Ca’
Foscari University of Venice, Via Torino 155, 30172 Mestre Venezia, Italy
| | - Mojtaba Gilzad Kohan
- Division
of Materials Science, Department of Engineering Sciences and Mathematics, Luleå University of Technology, 97187 Luleå, Sweden
| | - Alessandro Gradone
- CNR-IMM
Bologna Section, Via
Piero Gobetti 101, 40129 Bologna, Italy
- Chemistry
Department “Giacomo Ciamician”, University of Bologna, via Selmi 2, 40126 Bologna, Italy
| | - Raffaello Mazzaro
- CNR-IMM
Bologna Section, Via
Piero Gobetti 101, 40129 Bologna, Italy
| | - Vittorio Morandi
- CNR-IMM
Bologna Section, Via
Piero Gobetti 101, 40129 Bologna, Italy
| | - Alberto Vomiero
- Department
of Molecular Sciences and Nanosystems, Ca’
Foscari University of Venice, Via Torino 155, 30172 Mestre Venezia, Italy
- Division
of Materials Science, Department of Engineering Sciences and Mathematics, Luleå University of Technology, 97187 Luleå, Sweden
| | - Elisa Moretti
- Department
of Molecular Sciences and Nanosystems, Ca’
Foscari University of Venice, Via Torino 155, 30172 Mestre Venezia, Italy
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Ovcharov ML, Granchak VM. Photocatalytic Activation of Carbon Monoxide on Semiconductors and Derived Nanocomposites: Basic Principles and Mechanisms: A Review. THEOR EXP CHEM+ 2019. [DOI: 10.1007/s11237-019-09608-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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