La_(1-x)K_xMnO_3纳米粉体的制备与表征

Preparation and Characterization of La_(1-x)K_xMnO_3 Nanopowders

以硝酸镧、硝酸锰、硝酸钾为原料,以去离子水为溶剂,柠檬酸为络合剂,氨水调节溶液pH值,利用溶胶-凝胶法制备了La_(1-x)K_xMnO_3纳米粉体。用综合热分析仪确定前躯体的煅烧温度,用X射线衍射仪来表征粉体的晶体结构,用扫描电镜来表征粉体的微观形貌。结果表明:当K掺杂量为0.2时,前驱体在700℃煅烧2h能够得到单一晶相的La_(0.8)K_(0.2)MnO_3粉体,粉体为球状颗粒,分布较均匀,平均晶粒尺寸为25nm左右。

The La1-xKxMnO3 nano-powders were prepared by sol-gel method using lanthanum nitrate, manganese nitrate and potassium nitrate as raw materials, deionized water as the solvent, citric acid as the complexing agent and ammonia solution to adjust the p H value. The precursor＇s calcination temperature was determined by the integrated thermal analyzer. The crystal structure and morphologies of the particles were characterized by XRD and SEM. The results show that La0.8K0.2MnO3 powder with single crystal phase can be obtained by calcining the precursor at 700 °C for 2h. The powders were spherical with the average grain size of about 25 nm.