二维非晶碳材料的原子级加工
Atomic processing of two-dimensional amorphous carbon
郭云娜 1崔晗涛 1叶张然 1秦茜茜 2贾鹏 1邓蕾 1马崇崇 1邰超 1张利强 1温斌2
作者信息
- 1. Clean Nano Energy Center,State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao 066004,China
- 2. Center for Extreme Deformation Research,State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao 066004,China
- 折叠
摘要
二维非晶碳(2DAC)具有高导电性、高柔性和高化学稳定性等优异特性,在电子、传感器、催化剂、超导体、储能和能量转换等领域具有广阔的应用前景.然而,二维非晶碳很难直接制备,其形成机理和结构也存在许多争议.本文采用自上而下刻蚀的方法,在环境透射电镜中成功制备了二维非晶碳,在氧气(0.01 mbar)环境和电子束辐照下,将金刚石加热到650℃,金刚石经石墨化转变,最终转变为二维非晶碳.第一性原理计算表明,从金刚石到石墨是一个能量降低的过程,而从石墨向二维非晶碳转变是一个能量增加的过程,电子束辐照有利于克服该能垒.本研究制备了原子级精度的二维非晶碳,并利用原位表征技术揭示了其形成机理.本研究有助于从根本上理解二维非晶碳的形成过程和机理,也可为二维超薄非晶材料制备提供新的思路和见解.
Abstract
Two-dimensional amorphous carbon(2DAC)materials possess characteristics such as high conductivity,high flexibility,and chemical stability,making them promis-ing for applications in electronics,sensors,catalysts,super-conductors,energy storage,and energy conversion.However,it is still a challenge to directly synthesize 2D AC till now.Meanwhile,many controversies exist in their formation pro-cess and structure.Therefore,this article utilizes a top-down etching method to prepare 2D AC in environmental trans-mission electron microscope(ETEM).By employing electron beam irradiation combined with heating at 650℃ in an oxygen atmosphere(0.01 mbar),controllable fabrication of 2DAC is achieved.In this process,the raw diamond sheet first trans-forms into graphite,and as the reaction goes on,the amount of graphite increases,eventually transitioning into 2DAC.First-principles calculations indicate that it is an energy-favorable process from diamond to graphite.Although there is an en-ergy barrier for graphite-to-amorphous carbon transition,electron beam irradiation induces numerous defects that can overcome this barrier.This method not only fabricates 2D AC with atomic precision but also provides in-situ analysis of its formation process.The research findings contribute to a fundamental understanding of the formation process of 2DAC and offer new insights for the preparation of 2D ultrathin amorphous materials.
关键词
two-dimensional amorphous carbon(2DAC)/top-down/etching/diamondKey words
two-dimensional amorphous carbon(2DAC)/top-down/etching/diamond引用本文复制引用
出版年
2024
NETL
NSTL
万方数据