Sol-gel and polymeric membrane electrodes, based on thiacalix[4]arene as a neutral carrier, weresuccessfully developed for the detection of VO2+ in aqueous solutions. The sol-gel and PVCmembrane electrodes exhibited linear response with Nernstian slopes of 29.3 and 28.4 mV perdecade, respectively, within the vanadyl ion concentration ranges from 1.0 × 10-6 to 1.0 × 10-1mol dm-3 and from 1.0 × 1...

INTRODUCTION A sol-gel preparation involves f m t the formation of a sol, which is a suspension of solid particles in a liquid, then of a gel, which is a diphasic material with a solid encapsulating a liquid. The liquid can be removed from a gel by either conventional drying (such as by using an oven) to obtain a plojiict kLown as e xercgel, or hy drying with supercritical extraction (often ref...

The sol-gel method produces amorphous or crystalline thin gel films of metallic solid compounds by solidifying a sol formed by hydrolyzing and polymerizing a solution containing metallic compounds. Sol-gel processes are widely employed in the field of chemistry to prepare ceramic powders and thin films of hafnium oxide (HfO2) (Nishide et al., 2000) and zirconium oxide (ZrO2) ( Liu et al., 2002)...

For detection of phenolic compounds a simple amperometric biosensor based on tyrosinase immobilized in titania sol-gel/Nafion composite was employed. Titania sol-gel was mixed with Nafion (v/v) in ratios 1:1 (TiO2/NF-1/1) and 2:1 (TiO2/NF-2/1), v/v. Morphology of immobilization composites was characterized by scanning electron microscopy. Analytical performance of biosensors with Nafion and bas...

the photocatalytic coatings were prepared via incorporating the modified titania nanoparticles into epoxy-based inorganic-organic hybrid coatings. titania nanoparticles were first synthesized from tetra-n-butyl titanate using sol-gel methods by two different calcination treatments, i.e., in mild condition (80°c) and 500°c. the formed anatase nanoparticles were further modified as titania-silica...

tio2 nanoparticles, as a photocatalyst for oxidation of dimethyl methylphosphonate (dmmp) as an organophosphorus simulant of chemical warfare agent, were prepared by using sol-gel method. the prepared nanoparticles were then modified with transition metals in order to decrease the electron-hole recombination and increase the photocatalytic activity. transition metal ions including pt, pd and ni...

Three kinds of lipases (from Candida antarctica, Pseudomonas cepacia, and Pseudomonas fluorescens) were encapsulated in inorganic matrices by the sol-gel method in order to synthesize chiral compounds by kinetic resolution. Sol-gel lipases prepared with vinyltriethoxysilane had higher hydrolysis activity for 2-octyl acetate than those with other silane precursors: tetramethoxysilane, methyltrim...

Development of optical biosensors is an active area of research in the field of medical technology. Sol-gel matrices made from alkoxide silicates, tetraethyl orthosilicate (TEOS) appear to be suitable glassy host matrix for the sensing system. However, the major problem in the TEOS based sol-gel matrices is stability. So it is important to study dopant-matrix interaction as a function of time. ...

For the first time a top-down process was used to control the spatial location of Metal-Organic Frameworks on a surface. Deep X-ray lithography was utilised to micropattern a Zeolitic Imidazolate Framework layer on a sol-gel surface, with exposure hardening the sol-gel by inducing crosslinking while leaving the frameworks intact.

Titanium gels doped with water-soluble cationic porphyrin were synthesized by the sol–gel polymerization of Ti (OC4H9)4. In this work we investigate the spectroscopic properties along with SEM images of tetra carboxyl phenyl porphyrin when incorporated into porous matrix produced by the sol–gel technique. Keywords—TCPP; Titanium matrix; UV/Vis spectroscopy; SEM.