...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of power sources >Formation of Ce_(0.8)Sm_(0.2)O_(1.9) nanoparticles by urea-based low-temperature hydrothermal process
【24h】

Formation of Ce_(0.8)Sm_(0.2)O_(1.9) nanoparticles by urea-based low-temperature hydrothermal process

机译：尿素基低温水热法形成Ce_（0.8）Sm_（0.2）O_（1.9）纳米粒子

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The synthesis and formation mechanism of the nano-sized Ce_(0.8)Sm_(0.2)O_(1.9) particles prepared by a urea-based low-temperature hydrothermal process was investigated in this study. From ex situ X-ray diffraction and induced coupled plasma-atomic emission spectroscopy investigations, it was found that large quantities of cerium hydroxide co-precipitated with some samarium hydroxide at the initial stage of the hydrothermal process. The remaining Sm~(3+) ions in the solutions were further hydrolyzed and deposited on the surface of the cerium hydroxide-rich precipitates to form a core-shell-like structure. During the hydrothermal process, the core-shell-like structure transformed to a single cubic fluorite phase which is due to the incorporation of the deposited samarium hydroxide into the cerium oxide-rich core. Further, the average grain size of the synthesized nanocrystalline Ce_(0.8)Sm_(0.2)O_(1.9) was reduced with increasing the urea concentration in the solution. The density of the disk prepared with the synthesized Ce_(0.8)Sm_(0.2)O_(1.9) powders was found to increase with a decrease in the grain size of Ce_(0.8)Sm_(0.2)O_(1.9). The existence of SO_4~(2-) anions in the SDC powders prepared at low-urea concentration may result in the SDC disks with low density due to their decomposition during sintering process.
机译：研究了尿素基低温水热法制备的纳米Ce_（0.8）Sm_（0.2）O_（1.9）颗粒的合成及形成机理。从异位X射线衍射和诱导耦合等离子体原子发射光谱学研究发现，在水热过程的初期，大量的氢氧化铈与一些氢氧化sa共沉淀。溶液中剩余的Sm〜（3+）离子进一步水解并沉积在富含氢氧化铈的沉淀物表面上，形成核-壳状结构。在水热过程中，核-壳状结构转变为单立方萤石相，这是由于沉积的氢氧化mar掺入了富氧化铈的核中所致。此外，随着溶液中尿素浓度的增加，合成的纳米晶Ce_（0.8）Sm_（0.2）O_（1.9）的平均晶粒尺寸减小。发现用合成的Ce_（0.8）Sm_（0.2）O_（1.9）粉末制备的盘的密度随着Ce_（0.8）Sm_（0.2）O_（1.9）的晶粒尺寸的减小而增加。低尿素浓度制备的SDC粉末中SO_4〜（2-）阴离子的存在可能导致SDC盘由于在烧结过程中分解而密度低。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号