용매열법으로 출발물질의 농도를 변수로 차여 $BaTiO_3$ 분말을 합성하였다. 평균입자크기는 출발물질의 농도에 따라 비례하였는데 TiO_2를 기준으로 1/16M 농도에tj 59nm이었고 1/2M 농도에서는 89nm까지 증가하였다. 평균입자 크기가 89nm인 BT 분말에 대하여 리트벨트법에 의하여 분석한 결과 상분율은 정방정상 $75.5\%$이었고, 격자상수는 정방정상은 a=0.3999(nm), c=0.40319(nm)이고, 입방정상은 a=0.4015(nm)이었다. 이 분말을 $500^{circ}C$ 1시간 열처리 후 TEM분석을 한 결과, 분말 내부에 수산 이온들이 거의 존재하지 않음을 확인하였다.
Barium Titanate (BT) powders were synthesized by solvothermal method with an ethanol as a solvent. The average particle size was increased with the feedstock concentration: the size was 59 nm at $6.25{ imes}10^{-2}$ M and 89 nm at 0.5 M. The sample obtained at 0.5 M concentration was analysed by Rietveld refinement and the mole fraction of tetragonal phase was $75.5\%$ and lattice parameter of tetragonal phase was a=0.3999 (nm), c=0.4032 (nm), and cubic phase was a=0.4015 (nm). TEM analysis for the samples with condition of annealing at $500^{circ}C$ for I h showed that hydroxyl ions on oxygen sites were not found for these experimental conditions.
