非对称氮化多孔石墨烯纳米带的电输运性质  

The electrical transport properties of asymmetric C_(2)N-h2D nanoribbon

作　　者：夏蔡娟[1] 唐小洁 XIA Caijuan;TANG Xiaojie(School of Science,Xi’an Polytechnic University,Xi’an 710048,China)

机构地区：[1]西安工程大学理学院,陕西西安710048

出　　处：《纺织高校基础科学学报》2021年第3期74-80,共7页Basic Sciences Journal of Textile Universities

基　　金：国家自然科学基金(11004156);陕西省自然科学基金(2019JM-083);陕西省科技之星资助项目(2016KJXX-45)。

摘　　要：针对氮化多孔石墨烯纳米带(C_(2)N-h2D)性质单一,应用范围严重受限问题,设计了左右带宽比分别为WL∶WR=1.5∶1.0,WL∶WR=2.0∶1.0和WL∶WR=2.0∶1.5等3种非对称式锯齿型zC_(2)N-h2Ds结构。应用非平衡格林函数与密度泛函理论相结合的第一性原理方法,研究了其电输运性质。结果表明:非对称式结构会显著改善C_(2)N-h2D纳米带的输运性能。3种非对称式结构都呈现出了优异的负微分电阻效应(NDR)和整流特性。其中WL∶WR=1.5∶1结构下的输运性能最优,其电流的峰谷比高达272.3;在施加偏压Ub=0.2 V时,最大整流比高达Rmax=17.824×103。为设计和制备基于C_(2)N-h2D纳米带的纳米级NDR器件和整流器件提供了一定的理论指导。The C_(2)N-hD2 has such problems as onefold property,and severely limited application scope.Therefore,three kinds of asymmetric zigzag C_(2)N nanoribbon(zC_(2)N-h2D)structures with bandwidth ratios of WL∶WR=1.5∶1.0,WL∶WR=2.0∶1.0 and WL∶WR=2.0∶1.5 are designed,and their electrical transport properties are studied by using the first-principles method of non-equilibrium Green′s function combined with density functional theory.The results show that the asymmetric structure can significantly improve the transport performance of C_(2)N-h2D nanoribbons.The three asymmetric structures all exhibit excellent negative differential resistance effect(NDR)and rectification characteristics.The transport performance of the WL∶WR=1.5∶1.0 structure is the best,and the peak-to-valley ratio of the current is as high as 272.3,and the maximum rectification ratio is as high as Rmax=17.824×103 when the bias voltage is applied to Ub=0.2 V.These results provide some theoretical guidance for the design and fabrication of nanoscale NDR devices and rectifier devices based on C_(2)N-h2D nanoribbons.

关 键 词：氮化多孔石墨烯 分子电子学 整流特性 电输运特性 第一性原理 

分 类 号：O469[理学—凝聚态物理]