α-Fe2O_(3)的原子尺度界面结构与演变  

The atomic-scale interface structure and evolution ofα-Fe_(2)O_(3)

作　　者：马龙辉 孟爽 蒋仁辉 陈国旭佳 孟琪 李雷 赵培丽 张莹 王思铭 贾双凤 郑赫 王建波 MA Long-hui;MENG Shuang;JIANG Ren-hui;CHEN Guo-xu-jia;MENG Qi;LI Lei;ZHAO Pei-li;ZHANG Ying;WANG Si-ming;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;Suzhou Institute of Wuhan University,Suzhou Jiangsu 215123;Wuhan University Shenzhen Research Institute,Shenzhen Guangdong 518057,China)

机构地区：[1]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 [2]武汉大学苏州研究院,江苏苏州215123 [3]武汉大学深圳研究院,广东深圳518057

出　　处：《电子显微学报》2021年第5期529-536,共8页Journal of Chinese Electron Microscopy Society

基　　金：国家自然科学基金资助项目(Nos.52071237,12074290,51871169,51671148,11674251,51601132);江苏省自然科学基金资助项目(No.BK20191187);中央高校基本科研业务费专项资金(No.2042019kf0190);深圳市科创委基础研究面上项目(No.JCYJ20190808150407522);中国博士后科学基金资助项目(No.2019M652685)。

摘　　要：本文通过化学气相沉积法制备出α-Fe_(2)O_(3)纳米线,并利用透射电子显微术进行研究。发现,α-Fe_(2)O_(3)纳米线具有双晶结构,双晶界面呈"L"型,由界面Ⅰ、Ⅱ、Ⅲ组成,其中界面Ⅰ和界面Ⅱ分别由特定的晶面周期性交替排列,呈锯齿状;而界面Ⅲ则由多个晶面无序地排列构成,呈弯曲状。同时,电子能量损失谱表明无序的界面Ⅲ处存在Fe空位。进一步研究发现,在电子束辐照下单晶α-Fe_(2)O_(3)会还原成Fe_(3)O_(4),且存在两种特定的取向关系,分别为:(1)[0001]_(Fe_(2)O_(3))//[112]_(Fe_(3)O_(4)),[1120]_(Fe_(2)O_(3))//[131]_(Fe_(3)O_(4));(2)[1120]_(Fe_(2)O_(3))//[112]_(Fe_(3)O_(4)),[1102]_(Fe_(2)O_(3))//[131]_(Fe_(3)O_(4))。本文的工作有助于理解α-Fe_(2)O_(3)纳米材料的复杂结构。Single-crystalline and bicrystallineα-Fe_(2)O_(3) nanowires were successfully synthesized by chemical vapor deposition,and characterized by transmission electron microscopy.The nanowire bicrystal interface is found to be"L"shape consisting of three interfaces:Ⅰ,Ⅱ,andⅢ.InterfaceⅠandⅡare periodically arranged and alternately with specific crystal planes in a zigzag shape,respectively.InterfaceⅢis curved and composed of multiple crystal planes arranged disorderly.Meanwhile,the electron energy loss spectrum indicates that Fe vacancies exist at the disordered interface III.Detailed investigation reveals that single-crystallineα-Fe_(2)O_(3) could be reduced to Fe_(3)O_(4) under electron beam irradiation with two different orientation relationships:(1)[0001]Fe_(2)O_(3)//[112]_(Fe_(3)O_(4)),[1120]_(Fe_(2)O_(3))//[131]_(Fe_(3)O_(4));(2)[1120]_(Fe_(2)O_(3))//[112]_(Fe_(3)O_(4)),[1102]_(Fe_(2)O_(3))//[131]_(Fe_(3)O_(4)).Our work helps to understand the complex structure ofα-Fe_(2)O_(3) nanomaterials.

关 键 词：α-Fe_(2)O_(3) 双晶 界面 电子束辐照 透射电子显微学 

分 类 号：O611.4[理学—无机化学] TG14[理学—化学]