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Melis N, Loche D, Thakkar SV, Cutrufello MG, Sini MF, Sedda G, Pilia L, Frongia A, Casula MF. Magnetic Aerogels for Room-Temperature Catalytic Production of Bis(indolyl)methane Derivatives. Molecules 2024; 29:2223. [PMID: 38792085 PMCID: PMC11124404 DOI: 10.3390/molecules29102223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Revised: 05/05/2024] [Accepted: 05/06/2024] [Indexed: 05/26/2024] Open
Abstract
The potential of aerogels as catalysts for the synthesis of a relevant class of bis-heterocyclic compounds such as bis(indolyl)methanes was investigated. In particular, the studied catalyst was a nanocomposite aerogel based on nanocrystalline nickel ferrite (NiFe2O4) dispersed on amorphous porous silica aerogel obtained by two-step sol-gel synthesis followed by gel drying under supercritical conditions and calcination treatments. It was found that the NiFe2O4/SiO2 aerogel is an active catalyst for the selected reaction, enabling high conversions at room temperature, and it proved to be active for three repeated runs. The catalytic activity can be ascribed to both the textural and acidic features of the silica matrix and of the nanocrystalline ferrite. In addition, ferrite nanocrystals provide functionality for magnetic recovery of the catalyst from the crude mixture, enabling time-effective separation from the reaction environment. Evidence of the retention of species involved in the reaction into the catalyst is also pointed out, likely due to the porosity of the aerogel together with the affinity of some species towards the silica matrix. Our work contributes to the study of aerogels as catalysts for organic reactions by demonstrating their potential as well as limitations for the room-temperature synthesis of bis(indolyl)methanes.
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Affiliation(s)
- Nicola Melis
- Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, 09123 Cagliari, Italy
| | - Danilo Loche
- Nanostructures & Biotech Laboratory, Biological and Environmental Science and Engineering (BESE) Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Swapneel V. Thakkar
- Department of Chemical and Geological Sciences, University of Cagliari, 09042 Monserrato, Italy
| | | | - Maria Franca Sini
- Department of Chemical and Geological Sciences, University of Cagliari, 09042 Monserrato, Italy
| | - Gianmarco Sedda
- Department of Chemical and Geological Sciences, University of Cagliari, 09042 Monserrato, Italy
| | - Luca Pilia
- Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, 09123 Cagliari, Italy
| | - Angelo Frongia
- Department of Chemical and Geological Sciences, University of Cagliari, 09042 Monserrato, Italy
| | - Maria Francesca Casula
- Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, 09123 Cagliari, Italy
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Amairia C, Fessi S, Mhamdi M, Ghorbel A, Llorca J. Influence of the drying mode of support on the properties of Pd/Al 2O 3-ZrO 2 materials used for methane combustion. Sci Rep 2023; 13:20298. [PMID: 37985717 PMCID: PMC10662462 DOI: 10.1038/s41598-023-47630-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 11/16/2023] [Indexed: 11/22/2023] Open
Abstract
This work constitutes a new trial to enhance the properties of palladium supported on alumina modified with zirconium used as catalysts for methane combustion. The effect of the support drying mode is studied. For this aim, Al2O3-ZrO2 binary oxides with zirconium loading of 2 and 5% in weight were prepared using sol-gel process then dried under ordinary or supercritical conditions. Palladium with a loading of 0.5% was deposited on the support by wet impregnation. Several techniques have been used to investigate differences between the two types of the derived catalysts.
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Affiliation(s)
- C Amairia
- Laboratoire de Chimie des Matériaux et Catalyse, Département de Chimie, Faculté des Sciences de Tunis, Université Tunis-El Manar, Campus Universitaire, 2092, Tunis, Tunisia.
- Chemistry Department, College of Science, Al Baha University, Al Bahah, 65779, Saudi Arabia.
| | - S Fessi
- Laboratoire de Chimie des Matériaux et Catalyse, Département de Chimie, Faculté des Sciences de Tunis, Université Tunis-El Manar, Campus Universitaire, 2092, Tunis, Tunisia
| | - M Mhamdi
- Laboratory for the Application of Materials to the Environment, Water and Energy LAMEEE, Faculty of Sciences Gafsa, University of Gafsa, 2112, Gafsa, Tunisia
- Chemistry Department, College of Science and Arts Al Makhwah, Al Baha University, Al Bahah, Saudi Arabia
| | - A Ghorbel
- Laboratoire de Chimie des Matériaux et Catalyse, Département de Chimie, Faculté des Sciences de Tunis, Université Tunis-El Manar, Campus Universitaire, 2092, Tunis, Tunisia
| | - J Llorca
- Universitat Politècnica de Catalunya, Barcelone, Spain
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3
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PGM nanoparticle-based alumina aerogels for three-way catalyst applications. CATAL COMMUN 2022. [DOI: 10.1016/j.catcom.2022.106547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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4
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Farrell E, Jana SC. Surfactant-free oil-in-oil emulsion-templating of polyimide aerogel foams. INT POLYM PROC 2022. [DOI: 10.1515/ipp-2022-4248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
A surfactant-free oil-in-oil emulsion-templating method is presented for fabrication of monolithic polyimide aerogel foams using monomer systems that produce fast sol–gel transition. An aerogel foam is a high porosity (∼90%) material with coexisting meso- and macropores inherent to aerogels with externally introduced micrometer size open cells (macrovoids) that are reminiscent of foams. The macrovoids are introduced in polyimide sol using surfactant-free emulsion-templating of droplets of an immiscible liquid that are stabilized against coalescence by fast sol–gel transition. Three immiscible liquids – cyclohexane, n-heptane, and silicone oil – are considered in this work for surfactant-free emulsion-templating. The aerogel foam monoliths, recovered by supercritical drying, exhibit smaller size macrovoids when n-heptane and cyclohexane are used as emulsion-templating liquid, while the overall porosity and the bulk density show weak dependence on the emulsion-templating liquid.
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Affiliation(s)
- Erin Farrell
- School of Polymer Science and Polymer Engineering, University of Akron , Akron , OH 44325-0301 , USA
| | - Sadhan C. Jana
- School of Polymer Science and Polymer Engineering, University of Akron , Akron , OH 44325-0301 , USA
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5
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Kim BS, Choi J, Park YS, Qian Y, Shim SE. Semi-Rigid Polyurethane Foam and Polymethylsilsesquioxane Aerogel Composite for Thermal Insulation and Sound Absorption. Macromol Res 2022. [DOI: 10.1007/s13233-022-0026-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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6
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Smeets V, Gaigneaux EM, Debecker DP. Titanosilicate Epoxidation Catalysts: A Review of Challenges and Opportunities. ChemCatChem 2022. [DOI: 10.1002/cctc.202101132] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Valentin Smeets
- Institute of Condensed Matter and Nanosciences (IMCN) Université catholique de Louvain (UCLouvain) Place Louis Pasteur 1, Box L4.01.09 1348 Louvain-la-Neuve Belgium
| | - Eric M. Gaigneaux
- Institute of Condensed Matter and Nanosciences (IMCN) Université catholique de Louvain (UCLouvain) Place Louis Pasteur 1, Box L4.01.09 1348 Louvain-la-Neuve Belgium
| | - Damien P. Debecker
- Institute of Condensed Matter and Nanosciences (IMCN) Université catholique de Louvain (UCLouvain) Place Louis Pasteur 1, Box L4.01.09 1348 Louvain-la-Neuve Belgium
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Reduction of PVA Aerogel Flammability by Incorporation of an Alkaline Catalyst. Gels 2021; 7:gels7020057. [PMID: 34066884 PMCID: PMC8162340 DOI: 10.3390/gels7020057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/30/2021] [Accepted: 05/04/2021] [Indexed: 11/24/2022] Open
Abstract
Sodium hydroxide was used as a base catalyst to reduce the flammability of poly(vinyl alcohol) (PVA) aerogels. The base-modified aerogels exhibited significantly enhanced compressive moduli, likely resulting in decreased gallery spacing and increased numbers of “struts” in their structures. The onset of decomposition temperature decreased for the PVA aerogels in the presence of the base, which appears to hinder the polymer pyrolysis process, leading instead to the facile formation of dense char. Cone calorimetry testing showed a dramatic decrease in heat release when the base was added. The results indicate that an unexpected base-catalyzed dehydration occurs at fire temperatures, which is the opposite of the chemistry normally observed under typical synthesis conditions.
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Chong S, Riley BJ, Kuang W, Olszta MJ. Iodine Capture with Mechanically Robust Heat-Treated Ag-Al-Si-O Xerogel Sorbents. ACS OMEGA 2021; 6:11628-11638. [PMID: 34056318 PMCID: PMC8153970 DOI: 10.1021/acsomega.1c00852] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/13/2021] [Indexed: 06/12/2023]
Abstract
Various radionuclides are released as gases during reprocessing of used nuclear fuel or during nuclear accidents including iodine-129 (129I) and iodine-131 (131I). These isotopes are of particular concern to the environment and human health as they are environmentally mobile and can cause thyroid cancer. In this work, silver-loaded heat-treated aluminosilicate xerogels (Ag-HTX) were evaluated as sorbents for iodine [I2(g)] capture. After synthesis of the base NaAlSiO4 xerogel, a heat-treatment step was performed to help increase the mechanical integrity of the NaAlSiO4 gels (Na-HTX) prior to Ag-exchanging to create Ag-HTX xerogels. Samples were characterized by powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, Brunauer-Emmett-Teller analysis, gravimetric iodine loading, nanoindentation, and dynamic mechanical analysis. The structural and chemical analyses of Ag-HTX showed uniform distribution of Ag throughout the gel network after Ag-exchange. After I2(g) capture, the AgI crystallites were observed in the sorbent, verifying chemisorption as the primary iodine capture mechanism. Iodine loading of this xerogel was 0.43 g g-1 at 150 °C over 1 day and 0.52 g g-1 at 22 °C over 33 days. The specific surface area of Ag-HTX was 202 m2 g-1 and decreased to 87 m2 g-1 after iodine loading. The hardness of the Na-HTX was >145 times higher than that of the heat-treated aerogel of the same starting composition. The heat-treatment process increased Young's modulus (compressive) value to 40.8 MPa from 7.0 MPa of as-made xerogel, demonstrating the need for this added step in the sample preparation process. These results show that Ag-HTX is a promising sorbent for I2(g) capture with good iodine loading capacity and mechanical stability.
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Affiliation(s)
- Saehwa Chong
- Pacific Northwest National
Laboratory, Richland, Washington 99354, United States
| | - Brian J. Riley
- Pacific Northwest National
Laboratory, Richland, Washington 99354, United States
| | - Wenbin Kuang
- Pacific Northwest National
Laboratory, Richland, Washington 99354, United States
| | - Matthew J. Olszta
- Pacific Northwest National
Laboratory, Richland, Washington 99354, United States
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9
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Thermally stable surfactant-free ceria nanocubes in silica aerogel. J Colloid Interface Sci 2021; 583:376-384. [PMID: 33011407 DOI: 10.1016/j.jcis.2020.09.044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/01/2020] [Accepted: 09/12/2020] [Indexed: 11/23/2022]
Abstract
Surfactant-mediated chemical routes allow one to synthesize highly engineered shape- and size-controlled nanocrystals. However, the occurrence of capping agents on the surface of the nanocrystals is undesirable for selected applications. Here, a novel approach to the production of shape-controlled nanocrystals which exhibit high thermal stability is demonstrated. Ceria nanocubes obtained by surfactant-mediated synthesis are embedded inside a highly porous silica aerogel and thermally treated to remove the capping agent. Powder X-ray Diffraction and Scanning Transmission Electron Microscopy show the homogeneous dispersion of the nanocubes within the aerogel matrix. Remarkably, both the size and the shape of the ceria nanocubes are retained not only throughout the aerogel syntheses but also upon thermal treatments up to 900 °C, while avoiding their agglomeration. The reactivity of ceria is measured by in situ High-Energy Resolution Fluorescence Detected - X-ray Absorption Near Edge Spectroscopy at the Ce L3 edge, and shows the reversibility of redox cycles of ceria nanocubes when they are embedded in the aerogel. This demonstrates that the enhanced reactivity due to their prominent {100} crystal facets is preserved. In contrast, unsupported ceria nanocubes begin to agglomerate as soon as the capping agent decomposes, leading to a degradation of their reactivity already at 275 °C.
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Sakuma W, Yamasaki S, Fujisawa S, Kodama T, Shiomi J, Kanamori K, Saito T. Mechanically Strong, Scalable, Mesoporous Xerogels of Nanocellulose Featuring Light Permeability, Thermal Insulation, and Flame Self-Extinction. ACS NANO 2021; 15:1436-1444. [PMID: 33405895 DOI: 10.1021/acsnano.0c08769] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Scalability is a common challenge in the structuring of nanoscale particle dispersions, particularly in the drying of these dispersions for producing functional, porous structures such as aerogels. Aerogel production relies on supercritical drying, which exhibits poor scalability. A solution to this scalability limitation is the use of evaporative drying under ambient pressure. However, the evaporative drying of wet gels comprising nanoscale particles is accompanied by a strong capillary force. Therefore, it is challenging to produce evaporative-dried gels or "xerogels" that possess the specific structural profiles of aerogels such as mesoscale pores, high porosity, and high specific surface area (SSA). Herein, we demonstrate a structure of mesoporous xerogels with high porosity (∼80%) and high SSA (>400 m2 g-1) achieved by exploiting cellulose nanofibers (CNFs) as the building blocks with tunable interparticle interactions. CNFs are sustainable, wood-derived materials with high strength. In this study, the few-nanometer-wide CNFs bearing carboxy groups were structured into a stable network via ionic inter-CNF interaction. The outline of the resulting xerogels was then tailored into a regular, millimeter-thick, board-like structure. Several characterization techniques highlighted the multifunctionality of the CNF xerogels combining outstanding strength (compression E = 170 MPa, σ = 10 MPa; tension E = 290 MPa, σ = 8 MPa), moderate light permeability, thermal insulation (0.06-0.07 W m-1 K-1), and flame self-extinction. As a potential application of the xerogels, daylighting yet insulating, load-bearing wall members can be thus proposed.
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Affiliation(s)
- Wataru Sakuma
- Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Shunsuke Yamasaki
- Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Shuji Fujisawa
- Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Takashi Kodama
- Department of Mechanical Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Junichiro Shiomi
- Department of Mechanical Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kazuyoshi Kanamori
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Tsuguyuki Saito
- Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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11
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Alekseev ES, Alentiev AY, Belova AS, Bogdan VI, Bogdan TV, Bystrova AV, Gafarova ER, Golubeva EN, Grebenik EA, Gromov OI, Davankov VA, Zlotin SG, Kiselev MG, Koklin AE, Kononevich YN, Lazhko AE, Lunin VV, Lyubimov SE, Martyanov ON, Mishanin II, Muzafarov AM, Nesterov NS, Nikolaev AY, Oparin RD, Parenago OO, Parenago OP, Pokusaeva YA, Ronova IA, Solovieva AB, Temnikov MN, Timashev PS, Turova OV, Filatova EV, Philippov AA, Chibiryaev AM, Shalygin AS. Supercritical fluids in chemistry. RUSSIAN CHEMICAL REVIEWS 2020. [DOI: 10.1070/rcr4932] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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12
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Fang Z, Li P, Yu G. Gel Electrocatalysts: An Emerging Material Platform for Electrochemical Energy Conversion. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2003191. [PMID: 32830391 DOI: 10.1002/adma.202003191] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/02/2020] [Indexed: 06/11/2023]
Abstract
Seeking sustainable and cost-effective energy sources is one of the significant challenges for the sustainable development of modern society. To date, considerable expectations have been held for technologies, such as fuel cells and electrolyzers, where the performance strongly depends on electrochemical conversion processes that can generate and store chemical energy through the breaking or formation of chemical bonds. However, those advanced technologies are severely limited by the efficiency, selectivity, and durability of electrocatalysis. Thanks to their hierarchically porous architecture, compositional and structural tunability, and ease of functionalization, the family of gel materials opens exciting opportunities for advanced energy technologies. Unique advances in gel materials based on controllable compositions and functions enable gel electrocatalysts to potentially break the limitations of current materials, enhancing the device performance of electrochemical energy. Here, recent developments and challenges for nanostructured gel-based materials for electrocatalysis applications are summarized. Future possibilities and challenges for gel electrocatalysts in terms of synthesis and applications are also discussed.
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Affiliation(s)
- Zhiwei Fang
- Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Panpan Li
- Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Guihua Yu
- Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, TX, 78712, USA
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13
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Chong S, Riley BJ, Peterson JA, Olszta MJ, Nelson ZJ. Gaseous Iodine Sorbents: A Comparison between Ag-Loaded Aerogel and Xerogel Scaffolds. ACS APPLIED MATERIALS & INTERFACES 2020; 12:26127-26136. [PMID: 32401479 DOI: 10.1021/acsami.0c02396] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Silver-exchanged aluminosilicate aerogels and xerogels were investigated as gaseous iodine [I2(g)] sorbents. The structures, morphologies, compositions, and porosities of aerogels (as-made and heat-treated at 350 °C) and xerogels are compared by using powder X-ray diffraction (PXRD), scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and specific surface area (SSA) as well as pore size analyses. The as-made aerogels, xerogels, and heat-treated aerogels were ion exchanged with Ag in AgNO3 solutions of deionized water and methanol (5:1 by volume), and PXRD patterns showed the presence of nanocrystalline Ag0 after the Ag exchange. Gravimetric iodine loadings of Ag-aerogels and Ag-xerogels were 0.33-0.41 g g-1. The Ag-aerogels without heat treatment showed an ∼8 mass % higher iodine loading than Ag-impregnated xerogels and ∼3 mass % higher than heat-treated Ag-impregnated aerogels. All gels after iodine uptake showed the presence of AgI, indicating chemisorption of iodine to silver. The SSA values of the as-made gels were 420-600 m2 g-1 but decreased significantly to 34-120 m2 g-1 after Ag impregnation and iodine uptake. Overall, changes in physical and chemical properties of aerogels and xerogels after iodine uptake were similar and the differences in iodine loading capacities of the aerogels and xerogels were minimal, providing a driver for using xerogels due to their less complex synthesis process as compared to aerogels.
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Affiliation(s)
- Saehwa Chong
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Brian J Riley
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Jacob A Peterson
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Matthew J Olszta
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Zayne J Nelson
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
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14
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Zhou C, Shi J, Zhou W, Cheng K, Zhang Q, Kang J, Wang Y. Highly Active ZnO-ZrO2 Aerogels Integrated with H-ZSM-5 for Aromatics Synthesis from Carbon Dioxide. ACS Catal 2019. [DOI: 10.1021/acscatal.9b04309] [Citation(s) in RCA: 130] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Cheng Zhou
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Jiaqing Shi
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Wei Zhou
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Kang Cheng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Qinghong Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Jincan Kang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Ye Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
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15
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Talley SJ, Vivod SL, Nguyen BA, Meador MAB, Radulescu A, Moore RB. Hierarchical Morphology of Poly(ether ether ketone) Aerogels. ACS APPLIED MATERIALS & INTERFACES 2019; 11:31508-31519. [PMID: 31379150 DOI: 10.1021/acsami.9b09699] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The phase diagram for the thermoreversible gelation of poly(ether ether ketone) (PEEK) in 4-chlorophenol (4CP) was constructed over broad temperature and concentration ranges, revealing that PEEK is capable of dissolving and forming gels in both 4CP and dichloroacetic acid (DCA) up to a concentration of 25 wt %. Highly porous aerogels of PEEK were prepared through simple solvent exchange followed by one of two drying methods of solvent removal from the wet gel: freeze-drying or supercritical CO2 fluid extraction (SC-drying). The field-emission scanning electron microscopy analysis showed that gelation of PEEK in 4CP, followed by SC-drying, produced aerogels with well-defined lamellar aggregates as compared to less ordered aggregates formed from DCA. Mechanical properties (in compression) were shown to improve with increasing density, resulting in equivalent compressive moduli at comparable density, regardless of the preparation method (gelation solvent selection, concentration variation, or drying method). Nitrogen adsorption-desorption isotherms indicate that PEEK aerogels are comprised of mesopores (2-50 nm diameter pores) formed from stacked crystalline lamella. PEEK aerogels prepared using SC-drying exhibit higher Brunauer-Emmett-Teller surface areas than freeze-dried aerogels of comparable density. The ultra-small-angle X-ray scattering/small-angle X-ray scattering (SAXS)/wide-angle X-ray scattering analysis revealed a hierarchical morphology of the PEEK aerogels with structural features from PEEK crystallites to agglomerates of stacked lamella that spanned a wide range of length scales. SANS contrast-matching confirmed that the morphological origin of the principle scattering feature in PEEK aerogels is stacked crystalline lamella. Nitrogen sorption measurements of porosity and the specific surface area of the PEEK aerogels were correlated with the SAXS analysis to reveal a remarkably high surface area attributed to the platelet-like, lamellar morphology. Contact angle and contact angle hysteresis (CAH) revealed that low-density PEEK aerogels (ρ < 0.15 g/cm3) have water contact angles above the superhydrophobicity cutoff angle (>150°) and a very low CAH near 1°.
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Affiliation(s)
- Samantha J Talley
- Department of Chemistry, Macromolecules Innovation Institute (MII) , Virginia Tech , Blacksburg , Virginia 24061 , United States
| | - Stephanie L Vivod
- NASA Glenn Research Center , 21000 Brookpark Road , Cleveland , Ohio 44135 , United States
| | - Baochau A Nguyen
- Ohio Aerospace Institute , 22800 Cedar Point Road , Cleveland , Ohio 44142 , United States
| | - Mary Ann B Meador
- NASA Glenn Research Center , 21000 Brookpark Road , Cleveland , Ohio 44135 , United States
| | - Aurel Radulescu
- Jülich Center for Neutron Science, JCNS Outstation at MLZ , Forschungszentrum Jülich GmbH , Lichtenbergstrasse 1 , Garching 85747 , Germany
| | - Robert B Moore
- Department of Chemistry, Macromolecules Innovation Institute (MII) , Virginia Tech , Blacksburg , Virginia 24061 , United States
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Kreft S, Schoch R, Schneidewind J, Rabeah J, Kondratenko EV, Kondratenko VA, Junge H, Bauer M, Wohlrab S, Beller M. Improving Selectivity and Activity of CO2 Reduction Photocatalysts with Oxygen. Chem 2019. [DOI: 10.1016/j.chempr.2019.04.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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17
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Wei W, Hu H, Huang Z, Jiang Z, Lv X, Xie J, Kong L. BiPO4 nanorods anchored in biomass-based carbonaceous aerogel skeleton: A 2D-3D heterojunction composite as an energy-efficient photocatalyst. J Supercrit Fluids 2019. [DOI: 10.1016/j.supflu.2019.02.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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18
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Smeets V, van den Biggelaar L, Barakat T, Gaigneaux EM, Debecker DP. Macrocellular Titanosilicate Monoliths as Highly Efficient Structured Olefin Epoxidation Catalysts. ChemCatChem 2019. [DOI: 10.1002/cctc.201900028] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Valentin Smeets
- Institute of Condensed Matter and Nanosciences (IMCN) UCLouvain Place Louis Pasteur, 1, Box L4.01.09 1348 Louvain-la-Neuve Belgium
| | - Ludivine van den Biggelaar
- Institute of Condensed Matter and Nanosciences (IMCN) UCLouvain Place Louis Pasteur, 1, Box L4.01.09 1348 Louvain-la-Neuve Belgium
| | - Tarek Barakat
- Laboratory of Inorganic Materials Chemistry UNamur Rue de Bruxelles, 61 5000 Namur Belgium
| | - Eric M. Gaigneaux
- Institute of Condensed Matter and Nanosciences (IMCN) UCLouvain Place Louis Pasteur, 1, Box L4.01.09 1348 Louvain-la-Neuve Belgium
| | - Damien P. Debecker
- Institute of Condensed Matter and Nanosciences (IMCN) UCLouvain Place Louis Pasteur, 1, Box L4.01.09 1348 Louvain-la-Neuve Belgium
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19
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Sustainable, Low Flammability, Mechanically-Strong Poly(vinyl alcohol) Aerogels. Polymers (Basel) 2018; 10:polym10101102. [PMID: 30961027 PMCID: PMC6403961 DOI: 10.3390/polym10101102] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 10/02/2018] [Accepted: 10/02/2018] [Indexed: 11/23/2022] Open
Abstract
Poly(vinyl alcohol) (PVA), tannic acid (TA) and sodium hydroxide (NaOH) were used to prepare low-flammability, mechanically-strong aerogels via an environmentally-friendly freeze-drying method. Because of the strong interaction between TA and PVA through hydrogen bonds, PVA/TA/NaOH aerogels exhibited compressive moduli as high as 12.7 MPa, 20 times that of the control PVA aerogel. The microstructure of the aerogels in this study showed that the addition of NaOH disrupted the typical “card of house” aerogel structure, while the samples with TA showed a stereoscopic uniform structure. The thermal stabilities of aerogels were tested by thermogravimetric analysis, showing both a decrease on the onset of decomposition temperature, and a reduction in decomposition rate after initial char formation. The peak heat release rate and total heat release, as measured by cone calorimetry, dropped by 69% and 54%, respectively, after adding TA and NaOH.
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20
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In Situ Generation of Cu0 Supported on TiO2 Aerogel as a Catalyst for the Vapour Phase Hydrogenation of Nitrobenzene to Aniline. Catal Letters 2018. [DOI: 10.1007/s10562-018-2481-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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21
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Mesoporous SiO2-TiO2 epoxidation catalysts: Tuning surface polarity to improve performance in the presence of water. MOLECULAR CATALYSIS 2018. [DOI: 10.1016/j.mcat.2018.04.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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22
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Nanostructured Oxides Synthesised via scCO2-Assisted Sol-Gel Methods and Their Application in Catalysis. Catalysts 2018. [DOI: 10.3390/catal8050212] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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23
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Wang X, Li C, Shi Z, Zhi M, Hong Z. The investigation of an organic acid assisted sol–gel method for preparing monolithic zirconia aerogels. RSC Adv 2018; 8:8011-8020. [PMID: 35542027 PMCID: PMC9078517 DOI: 10.1039/c7ra13041d] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 02/15/2018] [Indexed: 11/29/2022] Open
Abstract
In our previous work, a citric acid assisted sol–gel method was developed for preparing monolithic metal oxide aerogels. Such method adopted citric acid as the gelator, which replaced the well-studied proton scavenger propylene oxide. In this work, we have further extended this “organic acid assisted” sol–gel method and investigated the gelation mechanism. Four different organic acids (butanedioic acid, l-malic acid, l-aspartic acid and mercaptosuccinic acid) with an identical main chain but different side groups were used as the gelators for preparing monolithic zirconia aerogels. It was found that complex interactions including covalent bond and coordination bond interactions between organic acids and zirconium ions were vital to give a rigid gel network. After supercritical drying, crystalline zirconia aerogels can be obtained with high surface areas over 330 m2 g−1 and large pore volumes over 3.574 cm3 g−1. The mechanism of the organic acid assisted sol–gel method free of propylene oxide for preparing monolithic zirconia aerogels was investigated in detail.![]()
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Affiliation(s)
- Xiaoqing Wang
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Chengyuan Li
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Zhenyu Shi
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Mingjia Zhi
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Zhanglian Hong
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
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24
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Nguyen BN, Meador MAB, Scheiman D, McCorkle L. Polyimide Aerogels Using Triisocyanate as Cross-linker. ACS APPLIED MATERIALS & INTERFACES 2017; 9:27313-27321. [PMID: 28737037 DOI: 10.1021/acsami.7b07821] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A family of polyimide (PI)-based aerogels is produced using Desmodur N3300A, an inexpensive triisocyanate, as the cross-linker. The aerogels are prepared by cross-linking amine end-capped polyimide oligomers with the triisocyanate. The polyimide oligomers are formulated using 2,2'-dimethylbenzidine, 4,4'-oxydianiline, or mixtures of both diamines, combined with 3,3',4,4'-biphenyltetracarboxylic dianhydride, and are chemically imidized at room temperature. Depending on the backbone chemistry, chain length, and polymer concentration, density of the aerogels ranged from 0.06 to 0.14 g/cm3 and Brunauer-Emmett-Teller surface areas ranged from 350 to 600 m2/g. Compressive moduli of these aerogels were as high as 225 MPa, which are comparable to, or higher than, those previously reported prepared with similar backbone structures but with other cross-linkers. Because of their lower cost and commercial availability as cross-linker, the aerogels may have further potential as insulation for building and construction, clothing, sporting goods, and automotive applications, although lower-temperature stability may limit their use in some aerospace applications.
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Affiliation(s)
- Baochau N Nguyen
- Ohio Aerospace Institute , 22800 Cedar Point Road, Brookpark, Ohio 44142, United States
| | - Mary Ann B Meador
- NASA Glenn Research Center , 21000 Brookpark Road, Cleveland, Ohio 44135, United States
| | - Daniel Scheiman
- Ohio Aerospace Institute , 22800 Cedar Point Road, Brookpark, Ohio 44142, United States
| | - Linda McCorkle
- Ohio Aerospace Institute , 22800 Cedar Point Road, Brookpark, Ohio 44142, United States
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25
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Bu Y, Feng J, Tian Y, Wang X, Sun M, Luo C. An organically modified silica aerogel for online in-tube solid-phase microextraction. J Chromatogr A 2017; 1517:203-208. [PMID: 28843602 DOI: 10.1016/j.chroma.2017.07.075] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 07/18/2017] [Accepted: 07/23/2017] [Indexed: 10/19/2022]
Abstract
Aerogels have received considerable attentions because of its porous, high specific surface, unique properties and environmental friendliness. In this work, an organically modified silica aerogel was functionalized on the basalt fibers (BFs) and filled into a poly(ether ether ketone) (PEEK) tube, which was coupled with high performance liquid chromatography (HPLC) for in-tube solid-phase microextraction (IT-SPME). The aerogel was characterized by scanning electron microscopy (SEM) and fourier transform infrared spectrometry (FT-IR). The extraction efficiency of the tube was systematically investigated and shown enrichment factors from 2346 to 3132. An automated, sensitive and selective method was developed for the determination of five estrogens. The linear range was from 0.03 to 100μgL-1 with correlation coefficients (r) higher than 0.9989, and low detection limits (LODs) were 0.01-0.05μgL-1. The relative standard deviations (RSDs) for intra-day and inter-day were less than 4.5% and 6.7% (n=6), respectively. Finally, the analysis method was successfully applied to detect estrogens in sewage and emollient water samples.
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Affiliation(s)
- Yanan Bu
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China
| | - Juanjuan Feng
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China
| | - Yu Tian
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China
| | - Xiuqin Wang
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China
| | - Min Sun
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
| | - Chuannan Luo
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
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26
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Arachchige IU, Armatas GS, Biswas K, Subrahmanyam KS, Latturner S, Malliakas CD, Manos MJ, Oh Y, Polychronopoulou K, P Poudeu PF, Trikalitis PN, Zhang Q, Zhao LD, Peter SC. Mercouri G. Kanatzidis: Excellence and Innovations in Inorganic and Solid-State Chemistry. Inorg Chem 2017; 56:7582-7597. [PMID: 28654276 DOI: 10.1021/acs.inorgchem.7b00933] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Over the last 3-4 decades, solid-state chemistry has emerged as the forefront of materials design and development. The field has revolutionized into a multidisciplinary subject and matured with a scope of new synthetic strategies, new challenges, and opportunities. Understanding the structure is very crucial in the design of appropriate materials for desired applications. Professor Mercouri G. Kanatzidis has encountered both challenges and opportunities during the course of the discovery of many novel materials. Throughout his scientific career, Mercouri and his group discovered several inorganic compounds and pioneered structure-property relationships. We, a few Ph.D. and postdoctoral students, celebrate his 60th birthday by providing a Viewpoint summarizing his contributions to inorganic solid-state chemistry. The topics discussed here are of significant interest to various scientific communities ranging from condensed matter to green energy production.
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Affiliation(s)
- Indika U Arachchige
- Department of Chemistry, Virginia Commonwealth University , Richmond, Virginia 23284-2006, United States
| | - Gerasimos S Armatas
- Department of Materials Science and Technology, University of Crete, Vassilika Vouton , Heraklion 71003, Greece
| | - Kanishka Biswas
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) , Jakkur P.O., Bangalore 560064, India
| | - Kota S Subrahmanyam
- Centre for Nano and Soft Matter Sciences , Jalahalli, Bangalore 560013, India
| | - Susan Latturner
- Department of Chemistry and Biochemistry, Florida State University , Tallahassee, Florida 32308, United States
| | - Christos D Malliakas
- Department of Chemistry, Northwestern University , 2145 North Sheridan Road, Evanston, Illinois 60208, United States
| | - Manolis J Manos
- Department of Chemistry, University of Ioannina , GR-45110 Ioannina, Greece
| | - Youngtak Oh
- Center for Environment, Health, and Welfare Research, Korea Institute of Science and Technology , Seongbuk-gu, Seoul 136-791, Republic of Korea
| | - Kyriaki Polychronopoulou
- Department of Mechanical Engineering, Khalifa University of Science, Technology, and Research , 127788 Abu Dhabi, United Arab Emirates
| | - Pierre F P Poudeu
- Materials Science and Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Pantelis N Trikalitis
- Department of Chemistry, University of Crete , Voutes Campus, 71003 Heraklion, Greece
| | - Qichun Zhang
- School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798, Singapore
| | - Li-Dong Zhao
- School of Material Science and Engineering, Beihang University , Beijing 10091, China
| | - Sebastian C Peter
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) , Jakkur P.O., Bangalore 560064, India
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27
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Adsorption of acetaldehyde at room temperature in a continuous system using silica synthesized by the sol-gel method. KOREAN J CHEM ENG 2017. [DOI: 10.1007/s11814-017-0170-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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28
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Hydrogen Production by Steam Reforming of Ethanol Over Mesoporous Ni–Al2O3–ZrO2 Catalysts. CATALYSIS SURVEYS FROM ASIA 2017. [DOI: 10.1007/s10563-017-9230-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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29
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Zhu Z, Snellings GMBF, Koebel MM, Malfait WJ. Superinsulating Polyisocyanate Based Aerogels: A Targeted Search for the Optimum Solvent System. ACS APPLIED MATERIALS & INTERFACES 2017; 9:18222-18230. [PMID: 28481507 DOI: 10.1021/acsami.7b03344] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Polyisocyanate based aerogels combine ultralow thermal conductivities with better mechanical properties than silica aerogel, but these properties critically depend on the nature of the gelation solvent, perhaps more so than on any other parameter. Here, we present a systematic study of the relationship between the polyurethane-polyisocyanurate (PUR-PIR) aerogel microstructure, surface area, thermal conductivity, and density and the gelation solvent's Hansen solubility parameters for an industrially relevant PUR-PIR rigid foam formulation. We first investigated aerogels prepared in acetone-dimethyl sulfoxide (DMSO) blends and observed a minimum in thermal conductivity (λ) and maximum in specific surface area for an acetone:DMSO ratio of 85:15 v/v. We then prepared PUR-PIR aerogels in 32 different solvent blends, divided into three series with δDispersion, δPolarity, and δH-bonding fixed at 15.94, 11.30, and 7.48 MPa1/2, respectively, corresponding to the optimum parameters for the acetone:DMSO series. The aerogel properties display distinct dependencies on the various solubility parameters: aerogels with low thermal conductivity can be synthesized in solvents with a high δH-bonding parameter (above 7.2) and δDispersion around 16.3 MPa1/2. In contrast, the δPolarity parameter is of lesser importance. Our study highlights the importance of the gelation solvent, clarifies the influence of the different solvent properties, and provides a methodology for a targeted search across the solvent chemical space based on the Hansen solubility parameters.
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Affiliation(s)
- Zhiyuan Zhu
- Laboratory for Building Energy Materials and Components, Swiss Federal Laboratories for Materials Science and Technology, EMPA , Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Geert M B F Snellings
- Sustainable Innovation Department, Recticel N.V. , Damstraat 2, Industriezone 7, 9230 Wetteren, Belgium
| | - Matthias M Koebel
- Laboratory for Building Energy Materials and Components, Swiss Federal Laboratories for Materials Science and Technology, EMPA , Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Wim J Malfait
- Laboratory for Building Energy Materials and Components, Swiss Federal Laboratories for Materials Science and Technology, EMPA , Überlandstrasse 129, 8600 Dübendorf, Switzerland
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30
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Chen Q, Wang H, Sun L. Preparation and Characterization of Silica Aerogel Microspheres. MATERIALS 2017; 10:ma10040435. [PMID: 28772795 PMCID: PMC5506966 DOI: 10.3390/ma10040435] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 04/14/2017] [Accepted: 04/18/2017] [Indexed: 11/16/2022]
Abstract
Silica aerogel microspheres based on alkali silica sol were synthesized using the emulsion method. The experimental results revealed that the silica aerogel microspheres (4–20 µm in diameter) were mesoporous solids with an average pore diameter ranging from 6 to 35 nm. The tapping densities and specific surface areas of the aerogel microspheres are in the range of 0.112–0.287 g/cm3 and 207.5–660.6 m2/g, respectively. The diameter of the silica aerogel microspheres could be tailored by varying the processing conditions including agitation rate, water/oil ratio, mass ratio of Span 80: Tween 80, and emulsifier concentration. The effects of these parameters on the morphology and textural properties of the synthesized silica aerogel microspheres were systematically investigated. Such silica aerogel microspheres can be used to prepare large-scale silica aerogels at an ambient pressure for applications in separation and high efficiency catalysis, which requires features of high porosity and easy fill and recovery.
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Affiliation(s)
- Qifeng Chen
- College of Materials Science & Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Hui Wang
- College of Materials Science & Engineering, South China University of Technology, Guangzhou 510640, China.
- Department of Chemical & Biomolecular Engineering and Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA.
| | - Luyi Sun
- Department of Chemical & Biomolecular Engineering and Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA.
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31
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The Evaluation of Synthesis Route Impact on Structure, Morphology and LT-WGS Activity of Cu/ZnO/Al2O3 catalysts. Catal Letters 2017. [DOI: 10.1007/s10562-017-2048-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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32
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Huber L, Zhao S, Malfait WJ, Vares S, Koebel MM. Fast and Minimal-Solvent Production of Superinsulating Silica Aerogel Granulate. Angew Chem Int Ed Engl 2017; 56:4753-4756. [DOI: 10.1002/anie.201700836] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Indexed: 11/05/2022]
Affiliation(s)
- Lukas Huber
- Building Energy Materials and Components Laboratory, Swiss Federal Laboratories for Materials Science and Technology, Empa; Überlandstrasse 129 8600 Dübendorf Switzerland
| | - Shanyu Zhao
- Building Energy Materials and Components Laboratory, Swiss Federal Laboratories for Materials Science and Technology, Empa; Überlandstrasse 129 8600 Dübendorf Switzerland
| | - Wim J. Malfait
- Building Energy Materials and Components Laboratory, Swiss Federal Laboratories for Materials Science and Technology, Empa; Überlandstrasse 129 8600 Dübendorf Switzerland
| | - Sirje Vares
- VTT Technical Research Center of Finland; Vuorimiehentie 5 Espoo, P.O. Box 1000 FI-02044 VTT Finland
| | - Matthias M. Koebel
- Building Energy Materials and Components Laboratory, Swiss Federal Laboratories for Materials Science and Technology, Empa; Überlandstrasse 129 8600 Dübendorf Switzerland
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33
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Huber L, Zhao S, Malfait WJ, Vares S, Koebel MM. Fast and Minimal-Solvent Production of Superinsulating Silica Aerogel Granulate. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201700836] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lukas Huber
- Building Energy Materials and Components Laboratory, Swiss Federal Laboratories for Materials Science and Technology, Empa; Überlandstrasse 129 8600 Dübendorf Switzerland
| | - Shanyu Zhao
- Building Energy Materials and Components Laboratory, Swiss Federal Laboratories for Materials Science and Technology, Empa; Überlandstrasse 129 8600 Dübendorf Switzerland
| | - Wim J. Malfait
- Building Energy Materials and Components Laboratory, Swiss Federal Laboratories for Materials Science and Technology, Empa; Überlandstrasse 129 8600 Dübendorf Switzerland
| | - Sirje Vares
- VTT Technical Research Center of Finland; Vuorimiehentie 5 Espoo, P.O. Box 1000 FI-02044 VTT Finland
| | - Matthias M. Koebel
- Building Energy Materials and Components Laboratory, Swiss Federal Laboratories for Materials Science and Technology, Empa; Überlandstrasse 129 8600 Dübendorf Switzerland
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34
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Viggiano RP, Williams JC, Schiraldi DA, Meador MAB. Effect of Bulky Substituents in the Polymer Backbone on the Properties of Polyimide Aerogels. ACS APPLIED MATERIALS & INTERFACES 2017; 9:8287-8296. [PMID: 28186399 DOI: 10.1021/acsami.6b15440] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
With unique advantages over inorganic aerogels including higher strengths and compressive moduli, greater toughness, and the ability to be fabricated as a flexible thin film, polymer aerogels have the potential to supplant inorganic aerogels in numerous applications. Among polymer aerogels, polyimide aerogels possess a high degree of high thermal stability as well as outstanding mechanical properties. However, while the onset of thermal decomposition for these materials is typically very high (greater than 500 °C), the polyimide aerogels undergo dramatic thermally induced shrinkage at temperatures well below their glass transition (Tg) or decomposition temperature, which limits their use. In this study, we show that shrinkage is reduced when a bulky moiety is incorporated in the polymer backbone. Twenty different formulations of polyimide aerogels were synthesized from 3,3,'4,4'-biphenyltetracarboxylic dianhydride (BPDA) and 4,4'-oxidianiline (ODA) or a combination of ODA and 9,9'-bis(4-aminophenyl)fluorene (BAPF) and cross-linked with 1,3,5-benzenetricarbonyl trichloride (BTC) in a statistically designed study. The polymer concentration, n-value, and molar concentration of ODA and BAPF were varied to demonstrate the effect of these variables on certain properties. Samples containing BAPF showed a reduction in shrinkage by as much as 50% after aging at elevated temperatures for 500 h compared to those made with ODA alone.
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Affiliation(s)
- Rocco P Viggiano
- NASA Glenn Research Center , 21000 Brookpark Road, Cleveland, Ohio 44135, United States
| | - Jarrod C Williams
- NASA Glenn Research Center , 21000 Brookpark Road, Cleveland, Ohio 44135, United States
| | - David A Schiraldi
- Case Western Reserve University , 2100 Adelbert Road, Cleveland, Ohio 44106, United States
| | - Mary Ann B Meador
- NASA Glenn Research Center , 21000 Brookpark Road, Cleveland, Ohio 44135, United States
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35
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Baatti A, Erchiqui F, Bébin P, Godard F, Bussières D. A two-step Sol-Gel method to synthesize a ladder polymethylsilsesquioxane nanoparticles. ADV POWDER TECHNOL 2017. [DOI: 10.1016/j.apt.2017.01.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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36
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Najafpour MM, Salimi S, Madadkhani S, Hołyńska M, Tomo T, Allakhverdiev SI. Nanostructured manganese oxide on silica aerogel: a new catalyst toward water oxidation. PHOTOSYNTHESIS RESEARCH 2016; 130:225-235. [PMID: 27037826 DOI: 10.1007/s11120-016-0247-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Accepted: 03/10/2016] [Indexed: 06/05/2023]
Abstract
Herein we report on the synthesis and characterization of nano-sized Mn oxide/silica aerogel with low density as a good catalyst toward water oxidation. The composite was synthesized by a simple and low-cost hydrothermal procedure. In the next step, we studied the composite in the presence of cerium(IV) ammonium nitrate and photo-produced Ru(bpy) 33+ as a water-oxidizing catalyst. The low-density composite is a good Mn-based catalyst with turnover frequencies of ~0.3 and 0.5 (mmol O2/(mol Mn·s)) in the presence of Ru(bpy) 33+ and cerium(IV) ammonium nitrate, respectively. In addition to the water-oxidizing activities of the composite under different conditions, its self-healing reaction in the presence of cerium(IV) ammonium nitrate was also studied.
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Affiliation(s)
- Mohammad Mahdi Najafpour
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan, 45137-66731, Iran.
- Center of Climate Change and Global Warming, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan, 45137-66731, Iran.
| | - Saeideh Salimi
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan, 45137-66731, Iran
| | - Sepideh Madadkhani
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan, 45137-66731, Iran
| | - Małgorzata Hołyńska
- Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften (WZMW), Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032, Marburg, Germany
| | - Tatsuya Tomo
- Department of Biology, Faculty of Science, Tokyo University of Science, Kagurazaka 1-3, Shinjuku-ku, Tokyo, 162-8601, Japan
- PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama, 332-0012, Japan
| | - Suleyman I Allakhverdiev
- Controlled Photobiosynthesis Laboratory, Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, Russia, 127276.
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290.
- Department of Plant Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, Russia, 119991.
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On the correlation between the porous structure and the electrochemical response of powdered and monolithic carbon aerogels as electrodes for capacitive deionization. J SOLID STATE CHEM 2016. [DOI: 10.1016/j.jssc.2016.06.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Nguyen BN, Cudjoe E, Douglas A, Scheiman D, McCorkle L, Meador MAB, Rowan SJ. Polyimide Cellulose Nanocrystal Composite Aerogels. Macromolecules 2016. [DOI: 10.1021/acs.macromol.5b01573] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Baochau N. Nguyen
- Ohio Aerospace
Institute, 22800 Cedar Point Road, Cleveland, Ohio 44142, United States
| | - Elvis Cudjoe
- Department
of Macromolecular Science and Engineering, Case Western Reserve University, 2100 Adelbert Road, Cleveland, Ohio 44106, United States
| | - Anna Douglas
- NASA Glenn Research
Center, 21000 Brookpark Road, Cleveland, Ohio 44135, United States
| | - Daniel Scheiman
- Ohio Aerospace
Institute, 22800 Cedar Point Road, Cleveland, Ohio 44142, United States
| | - Linda McCorkle
- Ohio Aerospace
Institute, 22800 Cedar Point Road, Cleveland, Ohio 44142, United States
| | - Mary Ann B. Meador
- NASA Glenn Research
Center, 21000 Brookpark Road, Cleveland, Ohio 44135, United States
| | - Stuart J. Rowan
- Department
of Macromolecular Science and Engineering, Case Western Reserve University, 2100 Adelbert Road, Cleveland, Ohio 44106, United States
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Macias C, Rasines G, García TE, Zafra MC, Lavela P, Tirado JL, Ania CO. Synthesis of Porous and Mechanically Compliant Carbon Aerogels Using Conductive and Structural Additives. Gels 2016; 2:E4. [PMID: 30674136 PMCID: PMC6318619 DOI: 10.3390/gels2010004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 01/04/2016] [Accepted: 01/08/2016] [Indexed: 11/28/2022] Open
Abstract
We report the synthesis of conductive and mechanically compliant monolithic carbon aerogels prepared by sol-gel polycondensation of melamine-resorcinol-formaldehyde (MRF) mixtures by incorporating diatomite and carbon black additives. The resulting aerogels composites displayed a well-developed porous structure, confirming that the polymerization of the precursors is not impeded in the presence of either additive. The aerogels retained the porous structure after etching off the siliceous additive, indicating adequate cross-linking of the MRF reactants. However, the presence of diatomite caused a significant fall in the pore volumes, accompanied by coarsening of the average pore size (predominance of large mesopores and macropores). The diatomite also prevented structural shrinkage and deformation of the as-prepared monoliths upon densification by carbonization, even after removal of the siliceous framework. The rigid pristine aerogels became more flexible upon incorporation of the diatomite, favoring implementation of binderless monolithic aerogel electrodes.
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Affiliation(s)
- Carlos Macias
- I + D Department, Nanoquimia S.L., 14014 Córdoba, Spain.
| | - Gloria Rasines
- I + D Department, Nanoquimia S.L., 14014 Córdoba, Spain.
| | - Tomas E García
- Campus Universitario, IUTA, Universidad de Oviedo, 33203 Gijón, Spain.
| | - María C Zafra
- Lab Química Inorgánica, University Cordoba, Campus de Rabanales, 14071 Córdoba, Spain.
| | - Pedro Lavela
- Lab Química Inorgánica, University Cordoba, Campus de Rabanales, 14071 Córdoba, Spain.
| | - José L Tirado
- Lab Química Inorgánica, University Cordoba, Campus de Rabanales, 14071 Córdoba, Spain.
| | - Conchi O Ania
- ADPOR Group, Instituto Nacional del Carbón (INCAR, CSIC), Oviedo 33001, Spain.
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Li Y, Hung F, Hope-Weeks LJ, Yan W. Fe/Al binary oxide aerogels and xerogels for catalytic oxidation of aqueous contaminants. Sep Purif Technol 2015. [DOI: 10.1016/j.seppur.2015.09.056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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41
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Subrahmanyam KS, Malliakas CD, Sarma D, Armatas GS, Wu J, Kanatzidis MG. Ion-Exchangeable Molybdenum Sulfide Porous Chalcogel: Gas Adsorption and Capture of Iodine and Mercury. J Am Chem Soc 2015; 137:13943-8. [DOI: 10.1021/jacs.5b09110] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
| | | | | | - Gerasimos S. Armatas
- Department
of Materials Science and Technology, University of Crete, Heraklion 71003, Crete, Greece
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Perissinotto AP, Awano CM, Donatti DA, de Vicente FS, Vollet DR. Mass and surface fractal in supercritical dried silica aerogels prepared with additions of sodium dodecyl sulfate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:562-568. [PMID: 25513729 DOI: 10.1021/la504272g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Silica wet gels were prepared from hydrolysis of tetraethoxysilane (TEOS) with additions of sodium dodecyl sulfate (SDS). The surfactant was removed after gelation. Wet gels exhibited mass-fractal structure with mass-fractal dimension D (typically around 2.25) in a length scale extending from a characteristic size ξ (typically about 10 nm) of the mass-fractal domains to a characteristic size a0 (typically between 0.3 and 0.4 nm) of the primary particles building up the fractal domains. ξ increased while D and a0 diminished slightly as the SDS quantity increased. Aerogels with typical specific surface of 1000 m(2)/g and density of 0.20 g/cm(3) were obtained by supercritical drying of the wet gels after washing with ethanol and n-hexane. The pore volume and the mean pore size increased with the increase of the SDS quantity. The aerogels presented most of the mass-fractal characteristics of the original wet gels at large length scales and exhibited at a higher resolution level at about 0.7 nm a crossover to a mass-surface fractal structure, with apparent mass-fractal dimension Dm ∼ 2.4 and surface-fractal dimension Ds ∼ 2.6, as inferred from small-angle X-ray scattering (SAXS) and nitrogen adsorption data.
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Affiliation(s)
- Amanda P Perissinotto
- IGCE, Departamento de Física, Unesp - Univ Estadual Paulista , Cx.P. 178, 13500-970 Rio Claro, SP, Brazil
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Das B, Renaud A, Volosin AM, Yu L, Newman N, Seo DK. Nanoporous delafossite CuAlO2 from inorganic/polymer double gels: a desirable high-surface-area p-type transparent electrode material. Inorg Chem 2015; 54:1100-8. [PMID: 25584858 DOI: 10.1021/ic5023906] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nanoporous structures of a p-type semiconductor, delafossite CuAlO(2), with a high crystallinity have been fabricated through an inorganic/polymer double-gel process and characterized for the first time via Mott-Schottky measurements. The effect of the precursor concentration, calcination temperature, and atmosphere were examined to achieve high crystallinity and photoelectrochemical properties while maximizing the porosity. The optical properties of the nanoporous CuAlO(2) are in good agreement with the literature with an optical band gap of 3.9 eV, and the observed high electrical conductivity and hole concentrations conform to highly crystalline and well-sintered nanoparticles observed in the product. The Mott-Schottky plot from the electrochemical impedance spectroscopy studies indicates a flat-band potential of 0.49 V versus Ag/AgCl. It is concluded that CuAlO(2) exhibits band energies very close to those of NiO but with electrical properties very desirable in the fabrication of photoelectrochemical devices including dye-sensitized solar cells.
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Affiliation(s)
- Barun Das
- Department of Chemistry and Biochemistry, Arizona State University , Tempe, Arizona 85287-1604, United States
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45
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Zhang Z, Gao Q, Liu Y, Zhou C, Zhi M, Hong Z, Zhang F, Liu B. A facile citric acid assisted sol–gel method for preparing monolithic yttria-stabilized zirconia aerogel. RSC Adv 2015. [DOI: 10.1039/c5ra13999f] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Citric acid was used as the cheap and environmental friendly gelation accelerator for preparation of monolithic zirconia aerogel.
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Affiliation(s)
- Zhiyi Zhang
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- PR China
| | - Qiuyue Gao
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- PR China
| | - Yi Liu
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- PR China
| | - Chunmei Zhou
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- PR China
| | - Mingjia Zhi
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- PR China
| | - Zhanglian Hong
- State Key Laboratory of Silicon Materials
- School of Materials Science and Engineering
- Zhejiang University
- Hangzhou 310027
- PR China
| | - Fan Zhang
- Aerospace Research Institute of Special Material and Processing Technology
- Beijing 100074
- PR China
| | - Bin Liu
- Aerospace Research Institute of Special Material and Processing Technology
- Beijing 100074
- PR China
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Osaki T, Yamada K, Watari K, Tajiri K. Superior thermal stability and oxygen storage capacity of ceria nanoparticles dispersed on alumina cryogel. REACTION KINETICS MECHANISMS AND CATALYSIS 2014. [DOI: 10.1007/s11144-014-0804-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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47
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Yan P, Zhou B, Du A. Synthesis of polyimide cross-linked silica aerogels with good acoustic performance. RSC Adv 2014. [DOI: 10.1039/c4ra08846h] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Kaur J, Dubey V, Suryanarayana NS, Kumar Swamy N, Pammi SVN, Ramakrishna PV. Thermoluminescence study of ZnS:Cu nanoparticles. RESEARCH ON CHEMICAL INTERMEDIATES 2013. [DOI: 10.1007/s11164-012-0905-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Schäfer H, Brandt S, Milow B, Ichilmann S, Steinhart M, Ratke L. Zirconia-based Aerogels via Hydrolysis of Salts and Alkoxides: The Influence of the Synthesis Procedures on the Properties of the Aerogels. Chem Asian J 2013; 8:2211-9. [DOI: 10.1002/asia.201300488] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Indexed: 11/07/2022]
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