calcium doped nickel ferrite powders have been prepared by sol-gel combustion technique. metal nitrates, such as calcium nitrate, nickel nitrate and ferric nitrate, were used as the source materials and citric acid and polyvinyl alcohol were used as the burning agent and agglomeration reducing agent, respectively. the average crystallite size of the prepared ferrite was in the order of ~70- 92 ...

in this work facile sol-gel (pechni) method has been successfully established to synthesize zn4b6o13 nanocrystals which have cubic crystals with lattice parameter: a =7.48 a. the structure and morphology of the obtained material were studied by x-ray diffraction (xrd), infrared spectra (ir), scanning electron microscopy (sem) and photoluminescence analysis. the experimental results show a band ...

titanium dioxide nanocrystals were synthesized by sol-gel method at room temperature. titanium isoprophoxide and absolute ethanol were used as precursors to prepare the sol. the ph of the solution was adjusted by adding nitric acid and sodium hydroxide solution. the prepared tio2 nanocrystals were annealed at 325°c, 425°c and 525°c respectively. the effect of ph on the surface morphology and st...

Titanium dioxide nanocrystals were synthesized by sol-gel method at room temperature. Titanium isoprophoxide and absolute ethanol were used as precursors to prepare the sol. The pH of the solution was adjusted by adding nitric acid and sodium hydroxide solution. The prepared TiO2 nanocrystals were annealed at 325°C, 425°C and 525°C respectively. The effect of pH on the surface morphology and st...

The vapor diffusion sol-gel (VDSG) method was employed for the room-temperature synthesis of ~10 nm, aliovalently doped 0.4, 0.8, and 1.6 mol% La:BaTiO3 and 0.4, 0.6, and 1.2 mol% Dy:BaTiO3 nanocrystals. Maximum ensemble relative permittivities of 176 and 208 were observed in the 0.8 mol% La:BaTiO3 and the 1.2 mol% Dy:BaTiO3 nanocrystals, respectively, relative to 89 for undoped BaTiO3 (at 1 MH...

Nanocrystals of Titanium dioxide were prepared via sol-gel and solvothermal method. They were characterized by X-ray diffraction and Scanning Electron Microscopy studies. The anatase and rutile phase reflections of the Titanium dioxide nanocrystals were identified by X-ray diffraction data. The micro strain value of the nanocrystals were analysed by W-H plot method. Very small value of micro st...

We elucidate the crystalline nature and the three-dimensional orientation of isolated organic nanocrystals embedded in a sol-gel matrix, using a polarized nonlinear microscopy technique that combines two-photon fluorescence and second harmonic generation. This technique allows the distinction between monocrystalline structures and nanoscale polycrystalline aggregates responsible for incoherent ...

Silicon nitride nanocrystals (NCs) have been prepared via in situ nitridation of magnesium followed by a metathesis reaction with sol-gel derived silica particles. Highly luminescent, freestanding β-Si(3)N(4) NCs with complex surface chemistry dominated by Si-H and N-H moieties were isolated upon etching with hydrofluoric acid.

Silica xerogels containing Sm ions and SnO2 nanocrystals were prepared in a sol–gel process. The image of transmission electron microscopy (TEM) shows that the SnO2 nanocrystals are dispersed in the silica matrix. The X-ray diffraction (XRD) of the sample confirms the tetragonal phase of SnO2. The xerogels containing SnO2 nanocrystals and Sm 3+ ions display the characteristic emission of Sm ion...

Silica xerogels containing Sm ions and SnO2 nanocrystals were prepared in a sol–gel process. The image of transmission electron microscopy (TEM) shows that the SnO2 nanocrystals are dispersed in the silica matrix. The X-ray diffraction (XRD) of the sample confirms the tetragonal phase of SnO2. The xerogels containing SnO2 nanocrystals and Sm 3+ ions display the characteristic emission of Sm ion...