@article{Chen2020, 
author = {Hui Chen and De-Liang Bao and Dongfei Wang and Yande Que and Wende Xiao and Yu-Yang Zhang and Jiatao Sun and Shixuan Du and Hong-Jun Gao},
title = {Fabrication and manipulation of nanosized graphene homojunction with atomically-controlled boundaries},
year = {2020},
journal = {Nano Research},
volume = {13},
number = {12},
pages = {3286-3291},
keywords = {grain boundaries, homojunction, graphene nanoislands, manipulations, twisted stacking},
url = {https://www.sciopen.com/article/10.1007/s12274-020-3004-5},
doi = {10.1007/s12274-020-3004-5},
abstract = {Controlling the atomic configurations of structural defects in graphene nanostructures is crucial for achieving desired functionalities. Here, we report the controlled fabrication of high-quality single-crystal and bicrystal graphene nanoislands (GNI) through a unique top-down etching and post-annealing procedure on a graphite surface. Low-temperature scanning tunneling microscopy (STM) combined with density functional theory calculations reveal that most of grain boundaries (GBs) formed on the bicrystal GNIs are 5-7-5-7 GBs. Two nanodomains separated by a 5-7-5-7 GB are AB stacking and twisted stacking with respect to the underlying graphite substrate and exhibit distinct electronic properties, forming a graphene homojunction. In addition, we construct homojunctions with alternative AB/twisted stacking nanodomains separated by parallel 5-7-5-7 GBs. Remarkably, the stacking orders of homojunctions are manipulated from AB/twist into twist/twist type through a STM tip. The controllable fabrication and manipulation of graphene homojunctions with 5-7-5-7 GBs and distinct stacking orders open an avenue for the construction of GBs-based devices in valleytronics and twistronics.}
}