| Barium titanate ceramics have been the focus because of the excellent properties, and been applied in many fields. Such, the studies on preparation of barium titanate powder and ceramics have been widely carried out nowadays.In this work, nano-ceramic powder was synthesized by the mixed hydroxide method, and this method has advantages as follows: melted anhydrous mixed alkali as the solvent, cheap inorganic salt and oxide as reactants and low synthesis temperature 200°C at normal atmosphere. The influencing factors for synthesizing barium titanate and doped powder, and for sintering of barium titanate ceramics were studied.Firstly, the XRD and SEM results indicate nano powder is cubic barium titanate and the grain size is about 60-100 nm, and the preparation conditions have great impact on purification of barium titanate powder, and it is found that the optimum condition is 230°C for 24h by the comparison of different conditions.Secondly, Ba1-xSrxTiO3 powder with nano size was also synthesized by the mixed hydroxide method between 180°C-245°C.Thirdly, study on properties of doped nano powders which were obtained by the mixed hydroxide method was also carried out, and the influence of doped ions on structure and morphology was analyzed. Barium titanate powders doped with niobium ion and cerium ion is of circular shape; Barium titanate powders doped with nickel ion, strontium ion, cobalt ion or magnesian ion is of square shape; Barium titanate powders doped with manganese ion is either of flake shape or of rod shape;Fourthly, powders that were made in experiment were pressed into circular pellets and then been sintered into ceramics. Also some tests were made in order to find a best sintering temperature.It is found that 1100°C is the optimum sintering temperature, because a biggest density and optimum electrical property can be botained at this temperature.
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