Organogels, hydrogels, and ionic gels have been investigated both in a theoretical and experimental manner. The research performed was focused on their synthesis and applications in high-performance ...chemistry and its important branches. All mentioned gels were characterized from structural and supramolecular points of view by FTIR, NMR, X-ray diffraction, and POM. The keywords proposed in this reprint were as follows: organogels, hydrogels, ionic gels, chitosan, and fractal analysis. These terms were extremely pertinent to this research piece, hereby presented. As a result, all reference themes, as well as those associated with them, were touched upon in this reprint. We mention that the articles in this selection focused on one or more of the topics listed above.
Porous silica‐based materials have burgeoning applications ranging from fillers and additives, to adsorbents, catalysts, and recently therapeutic agents and vaccines in nanomedicine. The ...preponderance of these materials is made by sol–gel processing wherein soluble silica precursors are reacted to form amorphous networks composed of siloxane bonds. The facile sol–gel approach allows for an unlimited variety of binary tertiary and more complex chemical compositions including organic ligands and networks resulting in so‐called organic–inorganic hybrid materials. Here, a brief review of the recent progress in sol–gel‐derived silica materials prepared as particles, thin films, biosilica/silica bioreplicas (of molecules, cells and organisms), and their related preparation, properties, and bioapplications is provided. First, it highlights the recent achievements of mesoporous silica nanoparticles in biomedical applications, including therapeutic agent delivery, multimodal imaging and theranostics, and bone tissue engineering and repair. Second, the research in evaporation‐induced self‐assembly (EISA)‐based mesostructured silica thin films and cell‐directed EISA in bio/nano interfaces for various bioapplications, such as bioactive coatings, biosensing, and living cell immobilization, has been reviewed. Third, the pioneering work in biomimetic silicification/immobilization of biomolecules and bio‐organisms and silica bioreplication of complex bio‐organisms is summarized. Finally, it is concluded with personal perspectives on the directions of future work on this field.
The most recent progress in sol–gel‐derived silica materials prepared as particles, thin films, biosilica, and silica bioreplicas (of molecules, cells, and organisms) is reviewed. This includes their related preparation, properties, and potential biological and biomedical applications.
Photocatalysts have been widely applied in the degradation of organic compounds using visible and ultraviolet radiation. Different synthesis approaches have been developed and optimized to produce ...efficient, eco-friendly, and inexpensive materials to photo-treat water samples contaminated with dyes, pigments, pesticides, and other organic pollutants. Over the last two decades magnetic materials have emerged as a potential alternative to facilitate catalyst isolation in heterogeneously catalyzed liquid-phase reactions. In this review, we focus on the discussion of several studies including the main synthesis processes and new protocol modifications for the fabrication of magnetic photocatalysts, and their impact on the catalyst morphology, efficiency, and recycling. Emphasis is given on the discussion of the synthesis strategies over last decade to produce photoactive catalysts including single-phase catalysts, composites, Multifunctional metal–organic framework materials, binary and ternary core–shell materials, and yolk–shell photocatalysts.
Highlights
A review on magnetic materials for photocatalysis is given.
Emphasis is given on sol–gel preparation methods utilized for the fabrication of magnetic photocatalysts.
Discussion on different material types of magnetic photocatalysts is presented.
Magnetic separation properties and efficiency are discussed based on the material structures.
Sol–gel technology is a contemporary advancement in science that requires taking a multidisciplinary approach with regard to its various applications. This book highlights some applications of the ...sol–gel technology, including protective coatings, catalysts, piezoelectric devices, wave guides, lenses, high-strength ceramics, superconductors, synthesis of nanoparticles, and insulating materials. In particular, for biotechnological applications, biomolecules or the incorporation of bioactive substances into the sol–gel matrix has been extensively studied and has been a challenge for many researchers. Some sol–gel materials are widely applied in light-emitting diodes, solar cells, sensing, catalysis, integration in photovoltaic devices, and more recently in biosensing, bioimaging, or medical diagnosis; others can be considered excellent drug delivery systems. The goal of an ideal drug delivery system is the prompt delivery of a therapeutic amount of the drug to the proper site in the body, where the desired drug concentration can be maintained. The interactions between drugs and the sol–gel system can affect the release rate. In conclusion, the sol–gel synthesis method offers mixing at the molecular level and is able to improve the chemical homogeneity of the resulting composite. This opens new doors not only regarding compositions of previously unattainable materials, but also to unique structures with different applications.
This study focuses on preparing PCM (phase change material) nanocapsules which contain PA (palmitic acid) as core and SiO2 as shell materials. For the first time encapsulation of phase change ...materials is synthesized in nano scale via the sol–gel method by changing the value of pH in the range of 11–12. The morphology and the mean size of three samples are compared and the influences of different pH values on the particle size studied. This investigation reveals that the encapsulation ratio of PA is increased from 83.25 to 89.55 percent by increasing the pH value in the range of 11–12. The nanoencapsulated PCMs are arranged uniformly and spherically with mean diameter sizes 183.7, 466.4 and 722.5 nm for pH values of 11, 11.5 and 12, respectively. A thermal cycling test is done by 2500 melting/freezing cycles to determine thermal reliability and chemical stability of the nanoencapsulated PCMs. The thermal conductivity of the encapsulated PA is significantly improved compared to pure PA. As a result, the prepared PA/SiO2 nanocapsules are appropriate PCMs for slurry thermal energy storage applications because of their acceptable thermal properties, good thermal reliability, chemical stability, uniform morphology and thermal conductivities.
•The spherical nanocapsules with homogenous size distribution were synthesized in nano scale with simple and convenient method.•Thermal energy storage properties, thermal stability and performance of encapsulated phase change material.•High latent heats were achieved in melting and freezing process.•Increasing thermal conductivity of phase change material.
Information, such as text printed on paper or images projected onto microfilm, can survive for over 500 years. However, the storage of digital information for time frames exceeding 50 years is ...challenging. Here we show that digital information can be stored on DNA and recovered without errors for considerably longer time frames. To allow for the perfect recovery of the information, we encapsulate the DNA in an inorganic matrix, and employ error‐correcting codes to correct storage‐related errors. Specifically, we translated 83 kB of information to 4991 DNA segments, each 158 nucleotides long, which were encapsulated in silica. Accelerated aging experiments were performed to measure DNA decay kinetics, which show that data can be archived on DNA for millennia under a wide range of conditions. The original information could be recovered error free, even after treating the DNA in silica at 70 °C for one week. This is thermally equivalent to storing information on DNA in central Europe for 2000 years.
Committing to memory: Digital information can endure thousands of years of storage when translated into ACGT nucleotide coding and encapsulated as DNA in silica glass spheres. This method was demonstrated with the digitalized Archimedes Palimpsest.
Sol‐gel route has shown its enormous potential in tissue engineering applications as an advantageous method for the production of bioactive glasses aimed at regenerating both hard and soft tissues. ...This review discusses the chemical aspects of the method with emphasis on the morphological, chemical, mechanical, and biological properties of sol‐gel derived materials. The attention will be particularly focused on sol‐gel bioactive glasses and sol‐gel foam scaffolds for bone regeneration. The advantages deriving from the versatility of the sol‐gel method compared to the traditional melt‐quenching route will be underlined in terms of bioactivity, compositions, and processing parameters.
The chemical protonation of graphitic carbon nitride (CN) solids with strong oxidizing acids, for example HNO3, is demonstrated as an efficient pathway for the sol processing of a stable CN colloidal ...suspension, which can be translated into thin films by dip/disperse‐coating techniques. The unique features of CN colloids, such as the polymeric matrix and the reversible hydrogen bonding, result in the thin‐film electrodes derived from the sol solution exhibiting a high mechanical stability with improved conductivity for charge transport, and thus show a remarkably enhanced photo‐electrochemical performance. The polymer system can in principle be broadly tuned by hybridization with desired functionalities, thus paving the way for the application of CN for specific tasks, as exemplified here by coupling with carbon nanotubes.
Going strong: Sol engineering of graphitic carbon nitride solids with strong oxidizing acids (e.g. HNO3) generates a stable colloidal suspension, which can be translated into thin films by dip/disperse‐coating techniques. The polymeric matrix and the reversible hydrogen bonding result in the thin‐film electrodes derived from the sol solution having high mechanical stability with improved conductivity for charge transport.
Sol–gel process is a very unique wet chemical method for producing advanced materials in various areas of research. An increasingly evolution trend of this process is to combine with other ...technologies, such as surface modification, hybridization, templating induction, self-assembly, and phase separation, for preparing new materials possessing controllable shape, unique microstructure, superior properties, and special application. The review aims to present the synthesis of several typical sol–gel-derived materials (monodisperse nanoparticles, hybrid coatings, hollow microspheres, aerogels, and porous monoliths) via sol–gel process combining with other technologies . Some examples of application of the sol–gel-derived materials are also included.
F-doped TiO2 is synthesized using a modified sol–gel method for visible photocatalytic degradation of MB with a high degradation rate of 91%.
•F-doped TiO2 are synthesized using a modified sol–gel ...method.•The photocatalytic degradation of methylene blue by F-doped TiO2 is investigated.•A high methylene blue degradation rate of 91% is achieved under visible light irradiation.
F-doped TiO2 (F-TiO2) were successfully synthesized using a modified sol–gel method. The morphologies, structures, and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV–vis absorption spectroscopy, and electrochemical impedance spectra, respectively. The results show that F-TiO2 exhibits an enhanced photocatalytic performance in the degradation of MB with a maximum degradation rate of 91% under visible light irradiation as compared with pure TiO2 (32%). The excellent photocatalytic activity is due to the contribution from the increased visible light absorption, promoted separation of photo-generated electrons and holes as well as enhanced photocatalytic oxidizing species with the doping of F in TiO2.
PDF
