作者
Hongyuan Yuan, Shuai Chang, Igor Bargatin, Ning C Wang, Daniel C Riley, Haotian Wang, Jared W Schwede, J Provine, Eric Pop, Zhi-Xun Shen, Piero A Pianetta, Nicholas A Melosh, Roger T Howe
发表日期
2015/10/14
期刊
Nano letters
卷号
15
期号
10
页码范围
6475-6480
出版商
American Chemical Society
简介
Low work function materials are critical for energy conversion and electron emission applications. Here, we demonstrate for the first time that an ultralow work function graphene is achieved by combining electrostatic gating with a Cs/O surface coating. A simple device is built from large-area monolayer graphene grown by chemical vapor deposition, transferred onto 20 nm HfO2 on Si, enabling high electric fields capacitive charge accumulation in the graphene. We first observed over 0.7 eV work function change due to electrostatic gating as measured by scanning Kelvin probe force microscopy and confirmed by conductivity measurements. The deposition of Cs/O further reduced the work function, as measured by photoemission in an ultrahigh vacuum environment, which reaches nearly 1 eV, the lowest reported to date for a conductive, nondiamond material.
学术搜索中的文章
H Yuan, S Chang, I Bargatin, NC Wang, DC Riley… - Nano letters, 2015