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Godshall GF, Rau DA, Williams CB, Moore RB. Additive Manufacturing of Poly(phenylene Sulfide) Aerogels via Simultaneous Material Extrusion and Thermally Induced Phase Separation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023:e2307881. [PMID: 38009658 DOI: 10.1002/adma.202307881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 10/30/2023] [Indexed: 11/29/2023]
Abstract
Additive manufacturing (AM) of aerogels increases the achievable geometric complexity, and affords fabrication of hierarchically porous structures. In this work, a custom heated material extrusion (MEX) device prints aerogels of poly(phenylene sulfide) (PPS), an engineering thermoplastic, via in situ thermally induced phase separation (TIPS). First, pre-prepared solid gel inks are dissolved at high temperatures in the heated extruder barrel to form a homogeneous polymer solution. Solutions are then extruded onto a room-temperature substrate, where printed roads maintain their bead shape and rapidly solidify via TIPS, thus enabling layer-wise MEX AM. Printed gels are converted to aerogels via postprocessing solvent exchange and freeze-drying. This work explores the effect of ink composition on printed aerogel morphology and thermomechanical properties. Scanning electron microscopy micrographs reveal complex hierarchical microstructures that are compositionally dependent. Printed aerogels demonstrate tailorable porosities (50.0-74.8%) and densities (0.345-0.684 g cm-3 ), which align well with cast aerogel analogs. Differential scanning calorimetry thermograms indicate printed aerogels are highly crystalline (≈43%), suggesting that printing does not inhibit the solidification process occurring during TIPS (polymer crystallization). Uniaxial compression testing reveals that compositionally dependent microstructure governs aerogel mechanical behavior, with compressive moduli ranging from 33.0 to 106.5 MPa.
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Affiliation(s)
- Garrett F Godshall
- Department of Chemistry, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Daniel A Rau
- Department of Mechanical Engineering, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Christopher B Williams
- Department of Mechanical Engineering, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Robert B Moore
- Department of Chemistry, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, VA, 24061, USA
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Del Río JI, Juhász L, Kalmár J, Erdélyi Z, Bermejo MD, Martín Á, Smirnova I, Gurikov P, Schroeter B. A greener approach for synthesizing metal-decorated carbogels from alginate for emerging technologies. NANOSCALE ADVANCES 2023; 5:6635-6646. [PMID: 38024290 PMCID: PMC10662111 DOI: 10.1039/d3na00444a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 10/11/2023] [Indexed: 12/01/2023]
Abstract
In the present work, a series of metal nanoparticle-decorated carbogels (M-DCs) was synthesized starting from beads of parent metal-crosslinked alginate aerogels (M-CAs). M-CAs contained Ca(ii), Ni(ii), Cu(ii), Pd(ii) and Pt(iv) ions and were converted to M-DCs by pyrolysis under a N2 atmosphere up to pyrolysis temperatures of TP = 600 °C. The textural properties of M-CAs are found to depend on the crosslinking ion, yielding fibrous pore networks with a high specific mesoporous volume and specific surface area SV (SV ∼ 480-687 m2 g-1) for M-CAs crosslinked with hard cations, Ca(ii), Ni(ii) and Cu(ii), and comparably loose networks with increased macroporosity and lower specific surface (SV ∼ 240-270 m2 g-1) for Pd(ii) and Pt(iv) crosslinked aerogels. The pyrolysis of M-CAs resulted in two simultaneously occurring processes: changes in the solid backbone and the growth of metal/metal oxide nanoparticles (NPs). The thermogravimetric analysis (TGA) showed a significant influence of the crosslinking cation on the decomposition mechanism and associated change in textural properties. Scanning electron microscopy-backscattered electron imaging (SEM-BSE) and X-ray diffraction revealed that metal ions (molecularly dispersed in the parent aerogels) formed nanoparticles composed of elementary metals and metal oxides in varying ratios over the course of pyrolytic treatment. Increasing the TP led to generally larger nanoparticles. The pyrolysis of the nickel-crosslinked aerogel (Ni-CA) preserved, to a large extent, the mesoporous structure and resulted in the evolution of fine (∼14 nm) homogeneously dispersed Ni/NiO nanoparticles. Overall, this work presents a green approach for synthesizing metal-nanoparticle containing carbon materials, useful in emerging technologies related to heterogeneous catalysis and electrocatalysis, among others.
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Affiliation(s)
- Juan I Del Río
- BioEcoUva, Bioeconomy Research Institute, PressTech Group, Department of Chemical Engineering and Environmental Technology, Universidad de Valladolid Prado de La Magdalena S/n 47011 Valladolid Spain +49 40 42878 3962
- Grupo Procesos Químicos Industriales, Department of Chemical Engineering, Universidad de Antioquia UdeA Calle 70 No. 52-21 Medellín 050010 Colombia
| | - Laura Juhász
- Department of Solid State Physics, University of Debrecen Egyetem sqr. 1 H-4032 Debrecen Hungary
| | - József Kalmár
- ELKH-DE Mechanisms of Complex Homogeneous and Heterogeneous Chemical Reactions Research Group, Department of Inorganic and Analytical Chemistry, University of Debrecen Egyetem tér 1. Debrecen H-4032 Hungary
| | - Zoltán Erdélyi
- Department of Solid State Physics, University of Debrecen Egyetem sqr. 1 H-4032 Debrecen Hungary
| | - María D Bermejo
- BioEcoUva, Bioeconomy Research Institute, PressTech Group, Department of Chemical Engineering and Environmental Technology, Universidad de Valladolid Prado de La Magdalena S/n 47011 Valladolid Spain +49 40 42878 3962
| | - Ángel Martín
- BioEcoUva, Bioeconomy Research Institute, PressTech Group, Department of Chemical Engineering and Environmental Technology, Universidad de Valladolid Prado de La Magdalena S/n 47011 Valladolid Spain +49 40 42878 3962
| | - Irina Smirnova
- Institute for Thermal Separation Processes, Hamburg University of Technology Eißendorfer Straße 38 21073 Hamburg Germany
| | - Pavel Gurikov
- Laboratory for Development and Modelling of Novel Nanoporous Materials, Hamburg University of Technology Eißendorfer Straße 38 21073 Hamburg Germany
- aerogel-it GmbH Albert-Einstein-Str. 1 49076 Osnabrück Germany
| | - Baldur Schroeter
- Institute for Thermal Separation Processes, Hamburg University of Technology Eißendorfer Straße 38 21073 Hamburg Germany
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Bakhori NM, Ismail Z, Hassan MZ, Dolah R. Emerging Trends in Nanotechnology: Aerogel-Based Materials for Biomedical Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:1063. [PMID: 36985957 PMCID: PMC10058649 DOI: 10.3390/nano13061063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/11/2023] [Accepted: 03/13/2023] [Indexed: 06/18/2023]
Abstract
At present, aerogel is one of the most interesting materials globally. The network of aerogel consists of pores with nanometer widths, which leads to a variety of functional properties and broad applications. Aerogel is categorized as inorganic, organic, carbon, and biopolymers, and can be modified by the addition of advanced materials and nanofillers. Herein, this review critically discusses the basic preparation of aerogel from the sol-gel reaction with derivation and modification of a standard method to produce various aerogels for diverse functionalities. In addition, the biocompatibility of various types of aerogels were elaborated. Then, biomedical applications of aerogel were focused on this review as a drug delivery carrier, wound healing agent, antioxidant, anti-toxicity, bone regenerative, cartilage tissue activities and in dental fields. The clinical status of aerogel in the biomedical sector is shown to be similarly far from adequate. Moreover, due to their remarkable properties, aerogels are found to be preferably used as tissue scaffolds and drug delivery systems. The advanced studies in areas including self-healing, additive manufacturing (AM) technology, toxicity, and fluorescent-based aerogel are crucially important and are further addressed.
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Affiliation(s)
- Noremylia Mohd Bakhori
- Faculty of Medicine and Health Sciences, Universiti Sains Islam Malaysia, Persiaran Ilmu, Putra Nilai, Nilai 71800, Negeri Sembilan, Malaysia
| | - Zarini Ismail
- Faculty of Medicine and Health Sciences, Universiti Sains Islam Malaysia, Persiaran Ilmu, Putra Nilai, Nilai 71800, Negeri Sembilan, Malaysia
| | - Mohamad Zaki Hassan
- Razak Faculty of Technology and Informatics, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur 54100, Selangor, Malaysia
| | - Rozzeta Dolah
- Department of Chemical Engineering, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur 54100, Selangor, Malaysia
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Hou Y, Chen J, Pan D, Zhao L. Directional-Freezing-Assisted In Situ Sol-Gel Strategy to Synthesize High-Strength, Fire-Resistant, and Hydrophobic Wood-Based Composite Aerogels for Thermal Insulation. Gels 2023; 9:gels9020170. [PMID: 36826340 PMCID: PMC9956576 DOI: 10.3390/gels9020170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 02/13/2023] [Accepted: 02/14/2023] [Indexed: 02/23/2023] Open
Abstract
The undesirable inherent natural characteristics of wood, such as low mechanical strength, flammability, and hygroscopicity, limit its potential applications in the thermal insulation industry. Overcoming these disadvantages can greatly expand the application scope of wood. A new attempt at wood modification, the directional-freezing-assisted in situ sol-gel strategy, was used to obtain wood-silica composite aerogels with the unique multi-level ordered porous structure of wood. This method enables silica nanoparticles to successfully replace lignin and facilitates the formation of strong hydrogen bonds between the silica and cellulose molecules. This results in improved mechanical properties for the composite with a density similar to that of natural wood but a mechanical strength that can be up to five times greater. The thermal conductivity coefficient is also reduced to 0.032 W (m·K)-1 compared to 0.066 W (m·K)-1 for natural wood. This aerogel composite exhibits improved fire resistance and hygroscopicity, with a decomposition temperature increase of approximately 45 °C compared to natural wood. Additionally, the composite demonstrates self-extinguishing behavior, with the structure remaining intact after combustion, and thus enhanced fire resistance. Simultaneously, the enhanced aerogel composite hydrophobicity, with water contact angle of up to 120°, is beneficial to a prominent thermal insulation performance in a high-humidity environment. The successful synthesis of wood-based composite aerogels provides a new and innovative approach for the utilization of wood resources in the thermal insulation industry.
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Georgiou E, Raptopoulos G, Anastopoulos I, Giannakoudakis DA, Arkas M, Paraskevopoulou P, Pashalidis I. Uranium Removal from Aqueous Solutions by Aerogel-Based Adsorbents-A Critical Review. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13020363. [PMID: 36678117 PMCID: PMC9866664 DOI: 10.3390/nano13020363] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/03/2023] [Accepted: 01/09/2023] [Indexed: 06/12/2023]
Abstract
Aerogels are a class of lightweight, nanoporous, and nanostructured materials with diverse chemical compositions and a huge potential for applications in a broad spectrum of fields. This has led the IUPAC to include them in the top ten emerging technologies in chemistry for 2022. This review provides an overview of aerogel-based adsorbents that have been used for the removal and recovery of uranium from aqueous environments, as well as an insight into the physicochemical parameters affecting the adsorption efficiency and mechanism. Uranium removal is of particular interest regarding uranium analysis and recovery, to cover the present and future uranium needs for nuclear power energy production. Among the methods used, such as ion exchange, precipitation, and solvent extraction, adsorption-based technologies are very attractive due to their easy and low-cost implementation, as well as the wide spectrum of adsorbents available. Aerogel-based adsorbents present an extraordinary sorption capacity for hexavalent uranium that can be as high as 8.8 mol kg−1 (2088 g kg−1). The adsorption data generally follow the Langmuir isotherm model, and the kinetic data are in most cases better described by the pseudo-second-order kinetic model. An evaluation of the thermodynamic data reveals that the adsorption is generally an endothermic, entropy-driven process (ΔH0, ΔS0 > 0). Spectroscopic studies (e.g., FTIR and XPS) indicate that the adsorption is based on the formation of inner-sphere complexes between surface active moieties and the uranyl cation. Regeneration and uranium recovery by acidification and complexation using carbonate or chelating ligands (e.g., EDTA) have been found to be successful. The application of aerogel-based adsorbents to uranium removal from industrial processes and uranium-contaminated waste waters was also successful, assuming that these materials could be very attractive as adsorbents in water treatment and uranium recovery technologies. However, the selectivity of the studied materials towards hexavalent uranium is limited, suggesting further developments of aerogel materials that could be modified by surface derivatization with chelating agents (e.g., salophen and iminodiacetate) presenting high selectivity for uranyl moieties.
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Affiliation(s)
- Efthalia Georgiou
- Radioanalytical and Environmental Chemistry Group, Department of Chemistry, University of Cyprus, P.O. Box 20537, Nicosia CY-1678, Cyprus
| | - Grigorios Raptopoulos
- Inorganic Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece
| | - Ioannis Anastopoulos
- Department of Agriculture, University of Ioannina, UoI Kostakii Campus, 47100 Arta, Greece
| | | | - Michael Arkas
- Demokritos National Centre for Scientific Research, Institute of Nanoscience and Nanotechnology, 15771 Athens, Greece
| | - Patrina Paraskevopoulou
- Inorganic Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece
| | - Ioannis Pashalidis
- Radioanalytical and Environmental Chemistry Group, Department of Chemistry, University of Cyprus, P.O. Box 20537, Nicosia CY-1678, Cyprus
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Advanced Polymeric Nanocomposites for Water Treatment Applications: A Holistic Perspective. Polymers (Basel) 2022; 14:polym14122462. [PMID: 35746038 PMCID: PMC9231113 DOI: 10.3390/polym14122462] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/14/2022] [Accepted: 06/14/2022] [Indexed: 12/15/2022] Open
Abstract
Water pollution remains one of the greatest challenges in the modern era, and water treatment strategies have continually been improved to meet the increasing demand for safe water. In the last few decades, tremendous research has been carried out toward developing selective and efficient polymeric adsorbents and membranes. However, developing non-toxic, biocompatible, cost-effective, and efficient polymeric nanocomposites is still being explored. In polymer nanocomposites, nanofillers and/or nanoparticles are dispersed in polymeric matrices such as dendrimer, cellulose, resins, etc., to improve their mechanical, thermophysical, and physicochemical properties. Several techniques can be used to develop polymer nanocomposites, and the most prevalent methods include mixing, melt-mixing, in-situ polymerization, electrospinning, and selective laser sintering techniques. Emerging technologies for polymer nanocomposite development include selective laser sintering and microwave-assisted techniques, proffering solutions to aggregation challenges and other morphological defects. Available and emerging techniques aim to produce efficient, durable, and cost-effective polymer nanocomposites with uniform dispersion and minimal defects. Polymer nanocomposites are utilized as filtering membranes and adsorbents to remove chemical contaminants from aqueous media. This study covers the synthesis and usage of various polymeric nanocomposites in water treatment, as well as the major criteria that influence their performance, and highlights challenges and considerations for future research.
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Effect of Precursor Nature and Sol-Gel Synthesis Conditions on TiO 2 Aerogel's Structure. Molecules 2021; 26:molecules26165090. [PMID: 34443677 PMCID: PMC8401230 DOI: 10.3390/molecules26165090] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 11/17/2022] Open
Abstract
The aim of this investigation was to synthesize high porosity TiO2 aerogel by applying sol-gel and subcritical drying methods and to identify the influence of reagent's nature and synthesis conditions on their structural and optical properties. Methods of XRD, FT-IR, BET, STA, SEM, and UV-vis were applied to investigate and compare the properties of synthesized TiO2 aerogels and to determine the most effective synthesis route. The structural parameters of the synthesized materials can be varied by changing the precursor type (titanium (IV), isopropoxide (TIP), or tetrabutylorthotitanate (TBOT)) and the nature of the solvent used for additional exchange (n-hexane (nH), cyclohexane (CH), or diethyl ether (DE)). All of the subcritical dried samples show the amorphous structure, which tends to crystallize into the anatase phase after calcination. The number of micro and mesopores and the specific surface area depends on the synthesis conditions. The pores with the highest diameter have been found for additionally nH exchanged and aged aerogel synthesized from precursor TIP. Despite the imperfections in the structure, the produced aerogels show structural and optical properties typical of the TiO2 structures mentioned in the literature.
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Xu J, Song W, Wu N, Tong J, Ren L. Preparation and characterization of chitosan/polyvinyl porous alcohol aerogel microspheres with stable physicochemical properties. Int J Biol Macromol 2021; 187:614-623. [PMID: 34314797 DOI: 10.1016/j.ijbiomac.2021.07.127] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/13/2021] [Accepted: 07/20/2021] [Indexed: 12/29/2022]
Abstract
Chitosan/polyvinyl alcohol (CS/PVA) porous aerogel microspheres with stable physicochemical properties were obtained by gelation and freeze-drying process, and modified by adding different content of polyvinyl alcohol (PVA) into the microspheres. The physicochemical properties of porous aerogel microspheres, including porosity, swelling degree, acid-base resistance and compression performance were compared with chitosan (CS) microspheres. The microspheres were characterized by scanning electronic microscopy, Fourier transform infrared spectra, X-ray diffraction and compression test. The results showed that the structure of hybrid aerogel microspheres could be controlled by adjusting the content of PVA. The increase of PVA content reduced the pore size of CS/PVA porous aerogel microspheres, promoted the roughness of the surface and formed more orderly pore distribution. The higher PVA content was, the greater the swelling degree of the CS/PVA porous microspheres was. Adding proper amount of PVA into the CS/PVA microspheres could improve their acid resistance, but reduce their alkali resistance. Furthermore, the porosity of CS/PVA microspheres containing 33.3% PVA was the highest (78.3%) and the best compression strength (0.0505 MPa) when compression depth was 60% of the maximum height.
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Affiliation(s)
- Jian Xu
- Key Laboratory of Bionic Engineering (Ministry of Education), College of Biological and Agricultural Engineering, Jilin University, Changchun 130022, China
| | - Wei Song
- Key Laboratory of Bionic Engineering (Ministry of Education), College of Biological and Agricultural Engineering, Jilin University, Changchun 130022, China
| | - Nan Wu
- Key Laboratory of Bionic Engineering (Ministry of Education), College of Biological and Agricultural Engineering, Jilin University, Changchun 130022, China
| | - Jin Tong
- Key Laboratory of Bionic Engineering (Ministry of Education), College of Biological and Agricultural Engineering, Jilin University, Changchun 130022, China
| | - Lili Ren
- Key Laboratory of Bionic Engineering (Ministry of Education), College of Biological and Agricultural Engineering, Jilin University, Changchun 130022, China.
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Effect of Process Conditions on the Properties of Resorcinol-Formaldehyde Aerogel Microparticles Produced via Emulsion-Gelation Method. Polymers (Basel) 2021; 13:polym13152409. [PMID: 34372011 PMCID: PMC8348565 DOI: 10.3390/polym13152409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/06/2021] [Accepted: 07/16/2021] [Indexed: 11/30/2022] Open
Abstract
Organic aerogels in the form of powder, microgranules and microsized particles receive considerable attention due to their easy fabrication, low process time and costs compared to their monolithic form. Here, we developed resorcinol-formaldehyde (RF) aerogel microparticles by using an emulsion-gelation method. The main objective of this study is to investigate the influence of curing time, stirring rate, RF sol:oil ratio and initial pH of the sol in order to control the size and properties of the microparticles produced. The emulsion-gelation of RF sol prepared with sodium carbonate catalyst in an oil phase at 60 °C was explored. RF microparticles were washed with ethanol to remove the oil phase followed by supercritical and ambient pressure drying. The properties of the dried RF microparticles were analyzed using FT-IR, N2 adsorption isotherm, gas pycnometry, wide angle X-ray scattering and scanning electron microscope. RF microparticles with high surface area up to 543 m2/g and large pore volume of 1.75 cm3/g with particle sizes ranging from 50–425 µm were obtained.
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Juhász L, Moldován K, Gurikov P, Liebner F, Fábián I, Kalmár J, Cserháti C. False Morphology of Aerogels Caused by Gold Coating for SEM Imaging. Polymers (Basel) 2021; 13:polym13040588. [PMID: 33669181 PMCID: PMC7919642 DOI: 10.3390/polym13040588] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/03/2021] [Accepted: 02/11/2021] [Indexed: 12/02/2022] Open
Abstract
The imaging of non-conducting materials by scanning electron microscopy (SEM) is most often performed after depositing few nanometers thick conductive layers on the samples. It is shown in this work, that even a 5 nm thick sputtered gold layer can dramatically alter the morphology and the surface structure of many different types of aerogels. Silica, polyimide, polyamide, calcium-alginate and cellulose aerogels were imaged in their pristine forms and after gold sputtering utilizing low voltage scanning electron microscopy (LVSEM) in order to reduce charging effects. The morphological features seen in the SEM images of the pristine samples are in excellent agreement with the structural parameters of the aerogels measured by nitrogen adsorption-desorption porosimetry. In contrast, the morphologies of the sputter coated samples are significantly distorted and feature nanostructured gold. These findings point out that extra care should be taken in order to ensure that gold sputtering does not cause morphological artifacts. Otherwise, the application of low voltage scanning electron microscopy even yields high resolution images of pristine non-conducting aerogels.
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Affiliation(s)
- Laura Juhász
- Department of Solid State Physics, University of Debrecen, Egyetem sqr. 1, H-4032 Debrecen, Hungary;
- Doctoral School of Physics, University of Debrecen, Egyetem sqr. 1, H-4032 Debrecen, Hungary
| | - Krisztián Moldován
- MTA-DE Redox and Homogeneous Catalytic Reaction Mechanisms Research Group, Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem sqr. 1, H-4032 Debrecen, Hungary; (K.M.); (I.F.)
- Doctoral School of Chemistry, University of Debrecen, Egyetem sqr. 1, H-4032 Debrecen, Hungary
| | - Pavel Gurikov
- Laboratory for Development and Modelling of Novel Nanoporous Materials, Hamburg University of Technology, Eißendorfer Straße 38, 21073 Hamburg, Germany;
| | - Falk Liebner
- Institute for Chemistry of Renewable Resources, University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Straße 24, A-3430 Tulln, Austria;
| | - István Fábián
- MTA-DE Redox and Homogeneous Catalytic Reaction Mechanisms Research Group, Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem sqr. 1, H-4032 Debrecen, Hungary; (K.M.); (I.F.)
| | - József Kalmár
- MTA-DE Redox and Homogeneous Catalytic Reaction Mechanisms Research Group, Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem sqr. 1, H-4032 Debrecen, Hungary; (K.M.); (I.F.)
- Correspondence: (J.K.); (C.C.); Tel.: +36-52-512-900 (J.K.); +36-52-316-073 (C.C.)
| | - Csaba Cserháti
- Department of Solid State Physics, University of Debrecen, Egyetem sqr. 1, H-4032 Debrecen, Hungary;
- Correspondence: (J.K.); (C.C.); Tel.: +36-52-512-900 (J.K.); +36-52-316-073 (C.C.)
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Feng J, Su BL, Xia H, Zhao S, Gao C, Wang L, Ogbeide O, Feng J, Hasan T. Printed aerogels: chemistry, processing, and applications. Chem Soc Rev 2021; 50:3842-3888. [PMID: 33522550 DOI: 10.1039/c9cs00757a] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
As an extraordinarily lightweight and porous functional nanomaterial family, aerogels have attracted considerable interest in academia and industry in recent decades. Despite the application scopes, the modest mechanical durability of aerogels makes their processing and operation challenging, in particular, for situations demanding intricate physical structures. "Bottom-up" additive manufacturing technology has the potential to address this drawback. Indeed, since the first report of 3D printed aerogels in 2015, a new interdisciplinary research area combining aerogel and printing technology has emerged to push the boundaries of structure and performance, further broadening their application scope. This review summarizes the state-of-the-art of printed aerogels and presents a comprehensive view of their developments in the past 5 years, and highlights the key near- and mid-term challenges.
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Affiliation(s)
- Junzong Feng
- Cambridge Graphene Centre, University of Cambridge, Cambridge CB3 0FA, UK.
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Yorov K, Kolesnik I, Romanova I, Mamaeva Y, Sipyagina N, Lermontov S, Kopitsa G, Baranchikov A, Ivanov V. Engineering SiO2–TiO2 binary aerogels for sun protection and cosmetic applications. J Supercrit Fluids 2021. [DOI: 10.1016/j.supflu.2020.105099] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Shi W, Ching YC, Chuah CH. Preparation of aerogel beads and microspheres based on chitosan and cellulose for drug delivery: A review. Int J Biol Macromol 2021; 170:751-767. [PMID: 33412201 DOI: 10.1016/j.ijbiomac.2020.12.214] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 12/24/2020] [Accepted: 12/29/2020] [Indexed: 12/11/2022]
Abstract
Spherical aerogels are not easily broken during use and are easier to transport and store which can be used as templates for drug delivery. This review summarizes the possible approaches for the preparation of aerogel beads and microspheres based on chitosan and cellulose, an overview to the methods of manufacturing droplets is presented, afterwards, the transition mechanisms from sol to a spherical gel are reviewed in detail followed by different drying processes to obtain spherical aerogels with porous structures. Additionally, a specific focus is given to aerogel beads and microspheres to be regarded as drug delivery carriers. Furthermore, a core/shell architecture of aerogel beads and microspheres for controlled drug release is described and subjected to inspire readers to create novel drug release system. Finally, the conclusions and outlooks of aerogel beads and microspheres for drug delivery are summarized.
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Affiliation(s)
- Wei Shi
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Yern Chee Ching
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Cheng Hock Chuah
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
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Chriti D, Raptopoulos G, Brandenburg B, Paraskevopoulou P. Large, Rapid Swelling of High- cis Polydicyclopentadiene Aerogels Suitable for Solvent-Responsive Actuators. Polymers (Basel) 2020; 12:polym12051033. [PMID: 32370122 PMCID: PMC7284835 DOI: 10.3390/polym12051033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 04/24/2020] [Accepted: 04/28/2020] [Indexed: 11/16/2022] Open
Abstract
High-cis polydicyclopentadiene (PDCPD) aerogels were synthesized using ring opening metathesis polymerization (ROMP) of dicyclopentadiene (DCPD) with a relatively air-stable ditungsten catalytic system, Na[W2(-Cl)3Cl4(THF)2]·(THF)3 (W2; (W 3 W)6+, a΄2e΄4), and norbornadiene (NBD)as a co-initiator. These aerogels are compared in terms of chemical structure and material properties with literature PDCPD aerogels obtained using well-established Ru-based alkylidenes as catalysts. The use of NBD as a co-initiator enhances the degree of crosslinking versus the more frequently used phenylacetylene (PA), yielding materials with a controlled molecular structure that would persist solvent swelling. Indeed, those PDCPD aerogels absorb selected organic solvents (e.g., chloroform, tetrahydrofuran) and swell rapidly, in some cases up to 4 times their original volume within 10 min, thus showing their potential for applications in chemical sensors and solvent-responsive actuators. The advantage of aerogels versus xerogels or dense polymers for these applications is their open porosity, which provides rapid access of the solvent to their interior, thus decreasing the diffusion distance inside the polymer itself, which in turn accelerates the response to the solvents of interest.
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Affiliation(s)
- Despoina Chriti
- Laboratory of Inorganic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece; (D.C.); (G.R.)
| | - Grigorios Raptopoulos
- Laboratory of Inorganic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece; (D.C.); (G.R.)
| | | | - Patrina Paraskevopoulou
- Laboratory of Inorganic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece; (D.C.); (G.R.)
- Correspondence: ; Tel.: +30-210-727-4381; Fax: +30-210-727-4782
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Paraskevopoulou P, Smirnova I, Athamneh T, Papastergiou M, Chriti D, Mali G, Čendak T, Raptopoulos G, Gurikov P. Polyurea-crosslinked biopolymer aerogel beads. RSC Adv 2020. [DOI: 10.1039/d0ra07337g] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Polyurea-crosslinked calcium alginate and chitosan aerogel beads: novel fibrous biopolymer-based aerogels.
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Affiliation(s)
- Patrina Paraskevopoulou
- Inorganic Chemistry Laboratory
- Department of Chemistry
- National and Kapodistrian University of Athens
- Athens
- Greece
| | - Irina Smirnova
- Institute of Thermal Separation Processes
- Hamburg University of Technology
- 21073 Hamburg
- Germany,
| | - Tamara Athamneh
- Institute of Thermal Separation Processes
- Hamburg University of Technology
- 21073 Hamburg
- Germany,
| | - Maria Papastergiou
- Inorganic Chemistry Laboratory
- Department of Chemistry
- National and Kapodistrian University of Athens
- Athens
- Greece
| | - Despoina Chriti
- Inorganic Chemistry Laboratory
- Department of Chemistry
- National and Kapodistrian University of Athens
- Athens
- Greece
| | - Gregor Mali
- National Institute of Chemistry
- 1000 Ljubljana
- Slovenia
| | - Tomaž Čendak
- National Institute of Chemistry
- 1000 Ljubljana
- Slovenia
| | - Grigorios Raptopoulos
- Inorganic Chemistry Laboratory
- Department of Chemistry
- National and Kapodistrian University of Athens
- Athens
- Greece
| | - Pavel Gurikov
- Laboratory for Development and Modelling of Novel Nanoporous Materials
- Hamburg University of Technology
- 21073 Hamburg
- Germany,
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