摘要
作为一种典型的近藤拓扑绝缘体,近年来六硼化钐(SmB6)材料受到了凝聚态物理和材料科学领域研究者的广泛关注。与块体材料相比,SmB6纳米材料由于具有更大的比表面积而拥有更为丰富的表面电子态,因此被认为是一个研究表面量子效应和物理机制的理想平台。由于场发射电流主要来源于纳米材料的表面态,所以研究SmB6纳米材料的场发射特性可以为研究其表面量子特性提供有益的参考。本研究利用化学气相沉积法,通过控制实验条件在硅衬底上分别实现了SmB6纳米带和纳米线薄膜的生长。研究结果表明:所制备的SmB6纳米线和纳米带分别为沿着[100]和[110]方向生长的立方单晶结构。场发射特性的测试结果发现:SmB6纳米带薄膜的开启电场为3.24 V/μm,最大电流密度达到了466.16μA/cm2,其场发射性能要优于纳米线薄膜。同时考虑到SmB6拥有很低的电子亲和势、高电导率和丰富的表面电子态,所以若可以进一步提高其场发射特性,那么很可能在冷阴极电子源领域有潜在应用。
Being a typical Kondo topological insulator,samarium hexaboride(SmB6)attracts much interest in condensed physics and material sciences in recent years.In comparison with their bulk counterparts,SmB6 nanostructures have more abundant surface electron states due to larger specific surface area,which are believed as idea platforms for studying surface quantum properties and physic mechanism.Through chemical vapor deposition(CVD),SmB6 nanobelt and nanowire films were respectively prepared on Si substrate.Both SmB6 nanowires and nanobelts are proven as the cubic single crystals,and their growth directions are,along[100]and[110],respectively.Field emission(FE)results show that SmB6 nanobelts have a turn-on field of 3.24 V/μm and their maximum current density arrives at 466.16μA/cm2,which are better than SmB6 nanowires.Considering that SmB6 nanostructures have lower electron affinity,higher electron conductivity and more abundant surface states,they are regarded as excellent cold cathode nanomaterials if their FE performances can be further improved.
作者
张彤
黎子娟
郭泽堃
田颜
林浩坚
许宁生
陈军
邓少芝
刘飞
ZHANG Tong;LI Zi-Juan;GUO Ze-Kun;TIAN Yan;LIN Hao-Jian;XU Ning-Sheng;CHEN Jun;DENG Shao-Zhi;LIU Fei(Guangdong Key Laboratory of Display Materials and Technologies,State Key Laboratory of Optoelectronic Materials and Technology,School of Eletronics and Information Technology,Sun Yat-sen University,Guangzhou 510275,China)
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2020年第2期199-204,共6页
Journal of Inorganic Materials
基金
科技部重大科学仪器研发专项(2013YQ12034506)
国家自然科学基金(51872337)
国家重大科学研究计划(2013CB933601)~~
关键词
六硼化钐
近藤拓扑绝缘体
纳米线
纳米带
场致电子发射
samarium hexaboride(SmB6)
topological Kondo insulator
nanowires
nanobelts
field emission(FE)
