TY - JOUR
T1 - Optical, electro-optical, electrical and dielectric characterization of nematic liquid crystal (E7) layers doped with graphene nanoparticles for electro-optics
AU - Marinov, Y. G.
AU - Hadjichristov, G. B.
AU - Rafailov, P. M.
AU - Lin, Shiuan-Huei
AU - Marinova, V. M.
AU - Petrov, A. G.
N1 - Publisher Copyright:
© Published under licence by IOP Publishing Ltd.
PY - 2019
Y1 - 2019
N2 - Thin (7 μm) layers of nanocomposites from graphene nanoflakes (GrFs) dispersed at concentrations of 10-3 wt.% into the nematic liquid crystal (NLC) E7 were characterized by various investigation techniques, such as Raman spectroscopy, impedance measurements and dielectric spectroscopy, as well as by electro-optical measurements (optical transmittance of the NLC layers versus the voltage of the applied external AC electric field). Conducting behaviour, dielectric permittivity and electric energy loss of our planar-aligned NLC layers at room temperature were analysed as a function of frequency in the range from 0.5 Hz to 1 MHz. The analysis of experimental data indicates that the molecular alignment through GrFs/NLC surface interactions is responsible for the reduction of the ionic conductivity of E7 NLC in the presence of GrFs. As compared to pure LC E7, this leads to improved characteristics for the studied nanocomposites, necessary in their practical applications in electro-optics.
AB - Thin (7 μm) layers of nanocomposites from graphene nanoflakes (GrFs) dispersed at concentrations of 10-3 wt.% into the nematic liquid crystal (NLC) E7 were characterized by various investigation techniques, such as Raman spectroscopy, impedance measurements and dielectric spectroscopy, as well as by electro-optical measurements (optical transmittance of the NLC layers versus the voltage of the applied external AC electric field). Conducting behaviour, dielectric permittivity and electric energy loss of our planar-aligned NLC layers at room temperature were analysed as a function of frequency in the range from 0.5 Hz to 1 MHz. The analysis of experimental data indicates that the molecular alignment through GrFs/NLC surface interactions is responsible for the reduction of the ionic conductivity of E7 NLC in the presence of GrFs. As compared to pure LC E7, this leads to improved characteristics for the studied nanocomposites, necessary in their practical applications in electro-optics.
UR - http://www.scopus.com/inward/record.url?scp=85064922375&partnerID=8YFLogxK
U2 - 10.1088/1742-6596/1186/1/012031
DO - 10.1088/1742-6596/1186/1/012031
M3 - Conference article
AN - SCOPUS:85064922375
SN - 1742-6588
VL - 1186
JO - Journal of Physics: Conference Series
JF - Journal of Physics: Conference Series
IS - 1
M1 - 012031
T2 - 20th Jubilee International School on Condensed Matter Physics: Physics and Applications of Advanced and Multifunctional Materials, ISCMP 2018
Y2 - 3 September 2018 through 7 September 2018
ER -