电子束诱导WO2.72单晶生长与还原

电子束诱导WO_2.72单晶生长与还原

王  严，文广玉，李  雷，刘辉辉，彭华雨，蒋仁辉，庄园林，贾双凤，郑  赫，王建波^*

（武汉大学物理科学与技术学院，电子显微镜中心，人工微结构教育部重点实验室和高等研究院,湖北  武汉430072）

摘  要    本文利用透射电子显微镜，观测电子束诱导WO_2.72单晶的生长与还原过程。通过对W纳米颗粒进行加热氧化处理（反应温度，400℃；反应时间，5 h），得到W/WO₃核壳球。实验中，利用会聚电子束辐照该核壳球，发现在球体边缘及外围有WO_2.72纳米棒、WO_2.72纳米片的生成或沉积现象。对生成的WO_2.72继续进行会聚电子束辐照，发现WO_2.72被还原为具有bcc结构的W，二者间的取向关系为：[001]WO2.72//[111]W,(010)WO2.72//(0-11)W 。本文提供了一种简单获得高结晶度WO_2.72的方法，同时结合其晶体结构对电子束辐照下的还原行为进行了深入探究。

关键词   WO_2.72；电子束；透射电子显微学

中图分类号：TN104.3;TB383;TG115.21⁺5.3 文献标识码：A    doi:10.3969/j.issn.1000-6281.2019.06.004

Electron-beam-induced growth and reduction of WO_2.72 single crystal

WANG Yan, WEN Guang-yu, LI Lei, LIU Hui-hui, PENG Hua-yu, JIANG Ren-hui, ZHANG Yuan-lin,JIA Shuang-feng, ZHENG He, WANG Jian-bo*

(School of Physics and Technology, Center for Electron Microscopy, MOE Key Laboratory of Artificial Micro- and Nano-structures, and Institute for Advanced Studies, Wuhan University, Wuhan Hubei 430072, China)

Abstract  Aid by transmission electron microscope, the growth and reduction processes of WO_2.72 single crystal are presented, induced bythe high energy focused the electron beam. The W/WO₃ core-shell spheres are prepared by heating W nanoparticles under 400 ℃ for 5 h. The W/WO₃ core-shell sphere is irradiated by a converged electron beam, and the formation or deposition of WO_2.72 nanorods and WO_2.72 nanosheets is observed at the edge and periphery of the sphere. The WO_2.72 is reduced into W with a bcc structure under further irradiation. The orientation relationship between WO_2.72 and W is ：[001]WO2.72//[111]W,(010)WO2.72//(0-11)W  . This paper provides a simple method to obtain high crystallinity WO_2.72 and combines its crystal structure to investigate the reduction behavior under the electron beam irradiation.

Keywords  WO_2.72; electron beam; transmission electron microscopy

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