六方相NaDyF_4微纳米晶的水热合成

Hydrothermal synthesis of hexagonal NaDyF_4 micro-nanocrystals

采用水热法合成六方相NaDyF4微纳米晶,考察反应温度、反应时间、F-和Dy3+的摩尔比等对产物晶型和形貌的影响。采用X线衍射仪(XRD)和扫描电子显微镜(SEM)对试样进行表征。结果表明:在水-乙醇-油酸体系中,固定水、乙醇和油酸的体积分别为10、12、6 mL,NaOH为0.5 g,调整F-和Dy3+的摩尔比值为4、5、7和10,220℃反应72 h,可以得到片状、短棒状、六棱柱状和长棒状等纯六方相NaDyF4微纳米晶。提出了六方相NaDyF4微纳米晶可能的生长机制。

Hexagonal NaDyF4 micro-nanocrystals was synthesized by hydrothermal method.The effects of the reaction temperature,reaction time and molar ratio of F-to Dy3＋ on the crystal structure and morphology of product were investigated.The sample was characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM）.Results showed that pure hexagonal phase NaDyF4 micro-nanocrystals with the morphologies,such as micro-nanoplates,short micro-nanorods,short micro-nanoprisms,and long micro-nanorods,could be obtained in the water-ethanol-oleic acid reaction system by changing F-to Dy3＋molar ratio of 4,5,7 and 10,when other synthetic parameters were set as reaction time of 72 h,reaction temperature of 220 ℃,water-ethanol-oleic acid of 10,12 and 6 mL and NaOH of 0.5 g.The possible growth mechanism of hexagonal NaDyF4 micro-nanocrystals was proposed.