Field emission properties of a graphene/polymer composite.
Thin graphene/polymer sheet composites were fabricated using easily soluble expanded graphite (ESEG), and their field emission (FE) parameters were examined. Due to the high dispersability of ESEG, a stable graphene suspension was prepared by ultrasonication in toluene without the need for a surfactant. The suspension consisted of exfoliated graphene sheets with a thickness of 1 - 2 nm. Using a calendering process, the solution was further shear mixed with ethyl cellulose to obtain a well-dispersed graphene/polymer composite. The composite was screen printed onto a conducing substrate to fabricate the FE cathode layers. The FE measurements were taken in a diode configuration at an applied electrostatic field and inter-electrode distance of 1.7 to 6 V/microm and approximately 200 microm, respectively. The threshold turn-on-field was approximately 3.5 V/microm at a current density of approximately 10 microA/cm2 with a corresponding mean field enhancement factor of 1350 +/- 50. Emission occurred mainly from the edges and bends of the graphene layers. The luminescence uniformity of the composite cathode layers was examined using a phosphor-coated anode.
SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 440746, Republic of Korea.
Shashikant P
SP
Patole
Jong Hak
JH
Lee
Jae Hong
JH
Park
Seong Man
SM
Yu
V G
VG
Makotchenko
A S
AS
Nazarov
V E
VE
Fedorov
Dong Wook
DW
Shin
Prashant S
PS
Alegaonkar
Mahendra A
MA
More
Ji-Beom
JB
Yoo
D002482:Cellulose / Q000737:chemistry*; D004553:Electric Conductivity; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry*; D049449:Luminescence; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D012666:Semiconductors; D055672:Static Electricity
D006108:Graphite; D002482:Cellulose