Growth of umbrella-like millimeter-scale single-crystalline graphene on liquid copper

TY - JOUR

T1 - Growth of umbrella-like millimeter-scale single-crystalline graphene on liquid copper

AU - Zhang, Chitengfei

AU - Tu, Rong

AU - Dong, Mingdong

AU - Li, Jun

AU - Yang, Meijun

AU - Li, Qizhong

AU - Shi, Ji

AU - Li, Haiwen

AU - Ohmori, Hitoshi

AU - Zhang, Song

AU - Zhang, Lianmeng

AU - Goto, Takashi

PY - 2019/9

Y1 - 2019/9

N2 - Novel single-crystalline umbrella-like graphene (ULG) domains with the diameter up to 0.6 mm were achieved on liquid copper by atmospheric pressure chemical vapor deposition (APCVD). ULG exhibits 6-fold symmetry with 6 ribs. Raman spectroscopy analysis revealed that the ULG was few-layer graphene with ultralow level of defects. Scanning Tunneling Microscope (STM) and selected area electron diffraction (SAED) results shown the single-crystalline nature of ULG. Transmission electron microscopy (TEM) shown the thickness of the panel was 3.5 nm and the thickness of the rib varied gradiently from 11.22 nm to 5.44 nm. The growth mechanism of the ULG was also explored by studying the influence of varied methane and hydrogen flow, which shows the ULG was formed during the nucleation stage. The larger flow of hydrogen supported decreasing the nucleation density of ULG, which was preferred for the formation of large domain ULG. Moreover, ULG partially immersed into liquid copper during the nucleation stage, thus, carbon atoms could reach each layer of ULG, leading to the continual growth of ULG graphene.

AB - Novel single-crystalline umbrella-like graphene (ULG) domains with the diameter up to 0.6 mm were achieved on liquid copper by atmospheric pressure chemical vapor deposition (APCVD). ULG exhibits 6-fold symmetry with 6 ribs. Raman spectroscopy analysis revealed that the ULG was few-layer graphene with ultralow level of defects. Scanning Tunneling Microscope (STM) and selected area electron diffraction (SAED) results shown the single-crystalline nature of ULG. Transmission electron microscopy (TEM) shown the thickness of the panel was 3.5 nm and the thickness of the rib varied gradiently from 11.22 nm to 5.44 nm. The growth mechanism of the ULG was also explored by studying the influence of varied methane and hydrogen flow, which shows the ULG was formed during the nucleation stage. The larger flow of hydrogen supported decreasing the nucleation density of ULG, which was preferred for the formation of large domain ULG. Moreover, ULG partially immersed into liquid copper during the nucleation stage, thus, carbon atoms could reach each layer of ULG, leading to the continual growth of ULG graphene.

UR - http://www.scopus.com/inward/record.url?scp=85066086847&partnerID=8YFLogxK

U2 - 10.1016/j.carbon.2019.05.013

DO - 10.1016/j.carbon.2019.05.013

M3 - Journal article

AN - SCOPUS:85066086847

SN - 0008-6223

VL - 150

SP - 356

EP - 362

JO - Carbon

JF - Carbon

ER -