To investigate the effect of oxygen pressure on the synthesis of LiNiO2 cathode material for Li secondary battery, powder was prepared by emulsion method and calcined at 750°C for 24 h under various oxygen gas pressures. LiNiO2 single phase could be synthesized under oxygen pressure of 101.3~103.3 kPa but not under air atmosphere. Cation mixing in Li site of LiNiO2 lowered as oxygen pressure increased and was saturated around 103.3 kPa. The lowest cation mixing, 7.0% of Ni3+ in the Li site was obtained at 750°C for 24 h under 103.3 kPa of oxygen pressure.

Structures, ferroelectric and piezoelectric properties of (Na0.5Bi0.5)0.90Ba0.10TiO3 ceramic sintered at different temperatures were investigated. The results confirm an important role of sintering temperature on the structure and electrical properties of the ceramic. It was found that the increase of sintering temperature in the range of 1110-1160 promoted the development of crystal structure and microstructural densification, leading to an improvement in ferroelectric properties, poling process and piezoelectric properties. Further increase of the sintering temperature above 1160 resulted in a slight deformation of ceramic specimens. With respect to sintering behavior and piezoelectric properties, a relatively narrow sintering temperature range near 1150 was ascertained to be preferred for the ceramic.

To overcome the difficulty of preparing the stoichiometric single phase calcium phosphate materials, ultrasonic spray pyrolysis was used to fabricate various calcium phosphates. Effect of the initial Ca/P ratios and pyrolysis temperature were investigated in preparation of single phase materials. Also thermal stability of the obtained powders was estimated with the heat treatment in the air. Crystallinity of the powders was analyzed using XRD and FT-IR. The HAp and β-TCP powders with single phase could be obtained from their stoichiometric Ca/P ratios of 1.50 and 1.67, respectively. These single phase powders with good crystallinity and stoichiometry were stable with respect to heat treatment up to 1000oC. The particle size of these powders would be controlled by the concentration of starting solution.