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In this work a new method has been developed to synthesize lithium nickel cobalt oxide (LiNi_0.8Co_0.2O₂) as cathode materials for rechargeable lithium batteries. It was clarified from these investigations that a sol-gel complex could be formed from basic cobalt carbonate, basic nickel carbonate, lithium carbonate by adding citrate as the complex agent. LiNi_0.8Co_0.2O₂ prepared using this sol-gel method shows a higher cycling capacity of ~190 mAh g⁻¹ and good rechargeability.

Titanium dioxide (TiO₂) is attractive because of their excellent photocatalytic activity, low cost, non-toxicity and good stability. Carbon doped titanium dioxide (TiO₂) was prepared using tetrabutyl titanate (TBT) as the source of titanium and tetrabutyl ammonium hydroxide (TABH) as the source of carbon by sel-gol method. The effect of carbon doping on the photocatalytic properties of titanium dioxide was investigated by the degradation of methyl orange under the light of mercury lamp and xenon lamp. The results show that carbon doping can improve the photocatalytic capacity of titanium dioxide under visible light and the optimum TABH additive amount was achieved.

It was already revealed that a sol-gel-derived titania forms an apatite on its surface in a simulated body fluid (SBF). It is, however, not clear what structure of titania gel is effective for inducing apatite nucleation on its surface. In the present study, apatite-forming ability of titania gels with different structures, which were formed in different media and heat-treated at different temperatures, were investigated in SBF. The titania gels heat-treated at 300°C took amorphous phases and did not form the apatite on their surfaces even after 14 days irrespective of the media. The titania gels, which were prepared in media containing no additive or acetylacetone and heat-treated at 500 to 800°C to precipitate anatase, formed the apatite on their surfaces within 7 days in SBF. The titania gels, which were prepared in a medium containing diethanolamine and heat-treated at 700 to 800°C to precipitate rutile, formed the apatite within 14 days in SBF. This indicates that a specific structure of titania such as anatase structure is effective for inducing apatite nucleation.

The development of high surface area and adequate porosity have been claimed as responsible for the high bioactivity exhibited by sol-gel glasses when immersed in a Simulated Body Fluid (SBF). However, the fast growth of a phosphate-rich layer on the surface of bioactive materials when exposed to physiological conditions, confers this layer the key role in determining the nature of the biomaterial/bone interface. The objective of this study has been to evaluate the surface properties of the phosphate layer developed on the surface of a SiO₂-CaO (CaO = 20 mol%) bioactive gel-glass by immersion into SBF. The growing process of the calcium phosphate layer has been monitored by SEM/EDS, TEM/ED and XPS. A calcium phosphate layer started to form very rapidly, covering most of the glass surface at only 3 h. Silicon is detected by XPS in the sample fully covered by calcium phosphate, which suggest that it is present during the whole crystallisation process at the phosphate/solution interface.

Tb Doped B₂O₃-SiO₂ phosphor were synthesized by the sol-gel (SG) method and the phase, morphology and luminescence properties of the phosphor were investigated. In this paper, the influence of B ions, annealing temperature on the luminescence properties was studying, and the prepared sample was characterized through Photoluminescence (PL) spectra, XRD, DTA-TG, FTIR and SEM. The powders exhibited emissions at 488, 544 and 585 nm, which were assigned to the ⁵D₄→⁷F₆, ⁵D₄→⁷F₅ and ⁵D₄→⁷F₄ transitions of Tb³⁺ from PL spectra. It can be clearly seen that luminescence intensity was enhanced, indicating that the symmetry of network is destroyed by B in the network under the infrared spectroscopy (IR). The emission intensity increases up to 400°C and then decreases. Thus, the critical temperature above which the temperature quenching becomes dominant was found to be 400°C.