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以CeCl_3·7H_2O为铈源、NH3·H2O为矿化剂、HCl为酸性调节剂,利用水热法成功制备了二氧化铈纳米颗粒.采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外-可见分光光度计(UV-Vis)、荧光分光光度计(PL)、拉曼光谱(Raman)和振动样品磁强计(VSM)等分析测试手段,对CeO_2纳米颗粒的晶相、形貌、光学和磁学性质进行了表征.XRD测试结果表明样品的晶格参数略高于块状CeO_2的,并随着pH值的增大而减小.所有样品的形貌均为球形.从紫外-可见吸收光谱中,估计出的样品直接带隙值小于块状CeO_2的,且此值随pH值的增加而增加.pH值为2时合成样品具有室温铁磁性,此性质的出现可能与Ce~(3+)和氧空位的存在有关.
The cerium oxide nanoparticles were successfully prepared by hydrothermal method using CeCl 3 · 7H 2 O as the cerium source, NH 3 · H 2 O as the mineralizer and HCl as the acidity modifier. XRD, SEM, , UV-Vis, PL, Raman and VSM were used to measure the crystal phase, shape and size of CeO_2 nanoparticles Appearance, optical and magnetic properties were characterized by XRD.The results of XRD showed that the lattice parameter of the sample was slightly higher than that of bulk CeO 2 and decreased with the increase of pH value.The morphology of all the samples was spherical In the UV-Vis absorption spectra, the estimated direct band gap of the sample is smaller than that of the bulk CeO 2, and this value increases with increasing pH. The synthesized sample has a room-temperature ferromagnetism at a pH of 2 and this property may be related to Ce ~ (3+) is related to the existence of oxygen vacancies.