Synthesis and evolution of potassium sodium niobate powders using an EDTA/citrate complexing sol-gel method
Potassium sodium niobate (KNN) powders were synthesized using a modified sol-gel method. The metal precursors used for the KNN synthesis were potassium carbonate, sodium carbonate, and niobium hydroxide. Ethylene glycol (EG) and ethylene diamine tetraacetic acid (EDTA)/citrate were used as the esterification and chelating agents, respectively. The effects of the amount of citric acid (CA), EG, and EDTA on the stability of the precursor sol were investigated. The powders and gels were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric-differential scanning calorimetry analysis. The results indicated that the stable precursor sol was formed when n(CA):n(Mn+) = 3:1, n(NH4-H2O):n(EDTA) = 1:3.5, and n(CA):n(EG) = 1:2. The xerogel was calcined at 500-950 ℃ to prepare the KNN powder. The pure perovskite phase of KNN with a cubic-like structure was synthesized at 850 ℃ from the precursor sol with the K/Na molar ratio of 1.2. The formation mechanism of the KNN perovskite phase was also discussed.
(K0.5Na0.5)NbO3 EDTA/citrate Sol-gel Submicron powder
Yang Cao Kongjun Zhu Hongjuan Zheng Jinhao Qiu Honghui Gu
State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, P. R. China
国内会议
中国颗粒学会超微颗粒专委会2011年年会暨第七届海峡两岸超微颗粒学术研讨会
辽宁丹东
英文
66-74
2011-08-08（万方平台首次上网日期，不代表论文的发表时间）