We have applied the sol-gel process to generate optical microstructures in glass using in-house developed sol-gel materials. The synthesis of our sol-gel glass materials is based on the formation of particles of controlled size from organo-metallic compounds. The overall shrinkage during annealing of the gel material is negligible and does not imply crack formation. Silica, titania and binar y ...

Sol–gel chemistry is an efficient tool to control the morphology and reactivity of solids. Drying is the crucial step due to the capillary forces exerted during the classic ambient drying process, which induces the collapse of the wet gel porosity. The use of N, N-dimethylformamide (DMF), a newly found DCCA were found to be effective in the sol–gel synthesis of crack-free silica gel monolith fr...

Micro electromechanical systems (MEMS) are finding uses in an increasing number of diverse applications. Currently the fabrication techniques used to produce such MEMS devices are primarily based on 2-D processing of thin films. The challenges faced by producing more complex structures (e.g. high aspect ratio, spans, and multi-material structures) require the development of new processing techn...

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 ...

We study a chemical gelation model in two dimensions which includes both monomer aggregations and bond fluctuations. Our numerical simulation shows that a sol-gel transition occurs when an initial monomer concentration is above a critical concentration. Fractal aggregates grow until the sol-gel transition occurs. After the gelation, however, bond fluctuations break the fractal structure and an ...

A comparing study on formation and microstructure features of aluminum titanate is investigated through both solid-state and sol-gel processes. Aluminum titanate formed by firing at 1350ºC and 1450ºC for 4h in solid-state process. In the sol-gel process formation of submicron sized particles is followed by addition of sucrose into the transparent sol. XRD analysis was confirmed the formation of...

To improve the corrosion protection of copper metal, 0.01M concentration of 1H-1,2,4-triazole-3-thiol (TAT) was incorporated into the hybrid sol-gel monolayers containing 3-glycidoxypropyltrimethoxysilane (GPTMS) and Tetraethoxysilane (TEOS). It was further subjected to hydrolysis and condensation reaction to form a sol-gel matrix. The TAT-doped hybrid sol-gel coating was applied over the c...

A novel, high hydrolysis ratio sol-gel route for the biocompatible production of macroporous silica gels is presented. This route exploits the two step nature of the gelation reaction to remove undesired alcohol by-products from an acidic aqueous sol prior to gelation. These alcohol-free sols will gel when the pH is raised to the physiologic range in a two-step, acid/base catalyzed process. Fur...

The leaching behavior of fluorescent siderophore, pyoverdin (iron biosensor), immobilized in acid-catalyzed sol-gel glass is examined. By varying the R value (molar ratio of water:silicon), three different formulations of pyoverdindoped sol-gel glass pellets (R = 5.6, 8.2, 10.8) were made with tetramethyl orthosilicate (TMOS). At three different aging times (2, 4, and 6 weeks), 7-day leaching e...