采用聚合物前驱体法,以柠檬酸(CA)为络合剂,乙二醇(EG)为酯化剂合成了纳米级(Na0.35K-0.65NbO3.研究了乙二醇用量对聚合物前驱体稳定性的影响,结果表明n(EG):n(CA)为2时能得到稳定凝胶,与乙二醇和柠檬酸聚酯化反应得到凝胶的理论配比一致。XRD分析表明聚合物前驱体在650℃煅烧2h可制得平均品粒尺寸为24nm左右,纯单斜相结构的(Na0.35K0.66)NbO3纳米粉体,该合成温度比传统固相法降低了约300℃。
With citdc acid as chelating agent and ethylene alcohol as etherification agent, (Na0.35K0.65)NbO3 nano powders were synthesized by polymeric precursor method. The effects of the amount of CA and EG on the stability of the precursor gel were investigated, the evolution of (Na0.35K0.65)NbO3 crystal phase was also investigated by XRD. The results showed that a homogeneous precursor gel was formed when n(CA) : n(metal ion)=1, n(EG) : n(CA)=2, and pure monoclinic phase NKN powders with the average size of about 24rim are obtained when the calcination temperature is 650℃, which is around 300℃ lower compared to the solid state reaction.