in this work firstly zno nanoparticles were synthesized via a simple precipitation method. at the second step titanium dioxide and silicon dioxide shell were synthesized on the core. for preparation zno-tio2-sio2 the sol product was calcinated at 500 ºc for 2h. properties of the product were examined by x-raydiffraction pattern (xrd), scanning electron microscope (sem) and fourier transform inf...

the stabilized zirconia with different cu contents synthesized via sol-gel method. the samples were prepared by hydrolysis and condensation of orgnomatelic sol. after that the result gels were dried at 80 °c and then calcined at various temperatures.  ِ the differential thermal analysis (dta), x-ray diffraction (xrd), field emission scanning electronic microscopy (fesem) and transmission electro...

in this research, a sol gel autocaombustion route has been proposedto synthesize alumina-zirconia composite powders, usingammonium bicarbonate as a new fuel. then the effect of calcinationtemperature on phase transformation and crystallite sizes wasinvestigated. to characterize the products xrd, tem and betanalyses were used. xrd patterns of as-synthesized powder andcalcined powders at 1100 ◦c ...

Sol-gel based biomaterials may be used for various applications, including biomedical ones. In this respect it is important to investigate the influence of sol-gel matrices on biological systems in order to establish their cytotoxic activity. The results of EPR studies of sol-gels are described in this work. They demonstrate that various defects are present in sol-gel matrices: surface defects,...

a useful nanophotocatalyst (la,s-tio2) was prepared by a sol-gel method and characterized by uv–vis diffuse reflectance spectroscopy (drs), x-ray diffraction (xrd), photoluminescence emission spectroscopy (pl) and scanning electron microscopy (fesem). the results showed that the la,s-tio2, which calcined at 550 °c, contained only anatase phaseand its crystal size was 23 nm. in addition, the fes...

In the field of polymer science, many kinds of polymeric material systems that show a sol-gel transition have been created. However, most systems are unidirectional stimuli-responsive systems that require physical signals such as a change in temperature. Here, we report on the design of a block copolymer solution that undergoes autonomous and periodic sol-gel transition under constant condition...

Thin films of Al2O3 have been deposited on ITO-coated glass substrates by a sol-gel dipcoat process. Aluminium isopropoxide (Al(OC3H7)3) was used as the Al source material. X-ray diffraction measurements show that these films are amorphous. Scanning electron microscopy and atomic force microscopy images of the films have revealed a relatively flat surface with no cracks. The dielectric properti...

The electrochemical entrapment of polyaniline (PANI) onto sol-gel derived tetraethylorthosilicate (TEOS) films deposited onto indium-tin-oxide (ITO) coated glass has been utilized for immobilization of lactate dehydrogenase (LDH). The performance of these sol-gel/PANI/LDH electrodes has been investigated as a function of the lactate concentration, applied potential, pH of the medium and interfe...

Colloidal suspensions are used to generate polymers or particles from which ceramic materials can be made by the sol-gel process. The precursors for preparation of a colloidal suspension consist of a metal element surrounded by various ligands (attached groups not including another metal). For example, common precursors for sol-gel synthesis of aluminum oxide include inorganic salts such as Al(...

We report on the fabrication of diffraction gratings in photosensitive sol–gel thin films by direct contact printing using a UV-mercury lamp. Titanium amplitude masks were used to replicate diffraction gratings into photosensitive sol–gel films by contact printing with an incoherent UV-light source. Gratings with 1-mm period were fabricated in sol–gel films. The diffraction efficiencies of each...