金属有机盐热分解法制备铌酸钾钠无铅压电薄膜

Preparation of Na_(0.5)K_(0.5)NbO_3 lead-free piezoelectric thin films with metal-organic salt thermo decomposition method

选用乙醇铌、乙酸钾、乙酸钠为原料,通过金属有机盐热分解法制备了Na0.5K0.5NbO3(NKN)无铅压电薄膜。研究了不同退火温度对NKN薄膜的晶体结构和形貌的影响。结果表明:当退火温度低于500℃时,所制NKN薄膜为无定形结构。650℃制备的NKN薄膜具有(100)晶面生长的择优取向;该薄膜的表面致密,颗粒尺寸分布均匀,10kHz的相对介电常数为258,介电损耗为0.05。该薄膜具有铁电体典型的电滞回线,剩余极化强度(Pr)和矫顽场强(EC)分别为3.45×10–6C/cm2和160×103V/cm。

Lead-free piezoelectric Na0.5K0.5NbO3 （NKN） thin films were prepared by metal-organic salt thermo decomposition method. Sodium acetate, potassium acetate and niobium pentaethoxide were selected as raw materials for the preparation of NKN precursor solutions. The structure and morphology of the NKN thin films at different annealing temperatures were studied. The results show that the NKN thin films are amorphous below 500 ℃. The NKN thin films annealed at 650 ℃ have a preferred orientation along with （l00） directions. The surpace of prepared NKN thin films is dense and the distribution of NKN particle size is uniform. The NKN thin films annealed at 650 ℃ exhibit relative permittivity of 258 and loss tangent of 0.05 at 10 kHz. The typical ferroelectric hysteretic loop is obtained with Pr and EC of 3. 45×10–6 C/cm2 and 160×103 V/cm, respectively.