The Power of Non-Hydrolytic Sol-Gel Chemistry: A Review
نویسندگان
چکیده
This review is devoted to non-hydrolytic sol-gel chemistry. During the last 25 years, non-hydrolytic sol-gel (NHSG) techniques were found to be attractive and versatile methods for the preparation of oxide materials. Compared to conventional hydrolytic approaches, the NHSG route allows reaction control at the atomic scale resulting in homogeneous and well defined products. Due to these features and the ability to design specific materials, the products of NHSG reactions have been used in many fields of application. The aim of this review is to present an overview of NHSG research in recent years with an emphasis on the syntheses of mixed oxides, silicates and phosphates. The first part of the review highlights well known condensation reactions with some deeper insights into their mechanism and also presents novel condensation reactions established in NHSG chemistry in recent years. In the second section we discuss porosity control and novel compositions of selected materials. In the last part, the applications of NHSG derived materials as heterogeneous catalysts and supports, luminescent materials and electrode materials in Li-ion batteries are described.
منابع مشابه
Novel Materials through Non-Hydrolytic Sol-Gel Processing: Negative Thermal Expansion Oxides and Beyond
Low temperature methods have been applied to the synthesis of many advanced materials. Non-hydrolytic sol-gel (NHSG) processes offer an elegant route to stable and metastable phases at low temperatures. Excellent atomic level homogeneity gives access to polymorphs that are difficult or impossible to obtain by other methods. The NHSG approach is most commonly applied to the preparation of metal ...
متن کاملLow temperature crystallisation of mesoporous TiO2.
Conducting mesoporous TiO2 is rapidly gaining importance for green energy applications. To optimise performance, its porosity and crystallinity must be carefully fine-tuned. To this end, we have performed a detailed study on the temperature dependence of TiO2 crystallisation in mesoporous films. Crystal nucleation and growth of initially amorphous TiO2 derived by hydrolytic sol-gel chemistry is...
متن کاملInvestigation of corrosion protection properties of TiO2-CdO nanocomposite coating prepared by sol-gel method on copper
the Sol–gel nanocomposite coatings have been investigated for copper metal as a potential replacement for the hazardous and banned hexavalent chromate conversion coatings. TiO2–CdO nanocomposite thin films were deposited on copper using the sol–gel method. The sol-gel coatings were prepared using a sol obtained by the hydrolysis and condensation of tetra-o-butyl titanate. They were doped with c...
متن کاملSynthesis and characterizations of CoTiO3-clay nanocomposites by sol-gel method
CoTiO3-clay nano-composites were synthesized via a conventional sol-gel method; the gel was calcinated at 500 - 800°C for 2 hours. The presence of rhombohedra phase of CoTiO3 in clay matrix was confirmed by XRD, FTIR, SEM. Cobalt titanate-clay nano-composites were prepared with 5-20%(w/w) by sol-gel method. The spectra results were investigated at 20% (w/w) concentration .The optimum condition ...
متن کامل