通过表面工程MXenes与二维半导体进行Schottky无障碍接触
Yuanyue Liu1, Hai Xiao1, William A Goddard1
1Materials and Process Simulation Center, ‡The Resnick Sustainability Institute, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|December 15, 2016
概括
两个维的MXenes显示为2D半导体的Schottky无障碍接触. 表面化学控制它们的工作功能, 实现高效的电荷注入和推进二维电子.
科学领域:
- 材料科学
- 凝聚物质物理学
- 纳米技术
背景情况:
- 像MXenes这样的二维材料对于下一代电子产品至关重要.
- 接口的接触阻力仍然是二维电子设备的一个重大挑战.
研究的目的:
- 调查MXenes作为2D半导体的潜在的Schottky无障碍金属接触.
- 了解表面化学对MXene电子属性的影响.
- 为二维电子中的接触阻力问题提供解决方案.
主要方法:
- 用第一原则计算来研究MXene的电子特性.
- 形成能量被计算为预测表面终端控制的合成路径.
主要成果:
- MXene表面化学 (O,OH,F终点) 强烈地决定了费米水平和工作功能.
- 表面二极管和微弱的费米平面定位方便了无Schottky障碍的电荷注入.
- 特定的O端和OH端MXenes能够有效地将孔或电子注入到二维半导体中.
结论:
- 对于二维半导体,MXenes可以作为有效的Schottky无障碍接触.
- 控制MXene表面终结是优化电子属性的关键.
- 这项研究为提高二维电子设备性能提供了途径.
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