論文がアクセプトされました(川俣先生・綱島先生・鈴木先生 共著)
Large In-Plane/Out-of-Olane Anisotropic Conduction in PEDOT-Based Hybrid
Films: Lamellar Assemblies Structured by Mono-Layered Nanosheets
S. Fujii, Y. Suzuki, J. Kawamata, R. Tsunashima
J. Mater. Chem. C, 2015, 3, 7153-7158
DOI : 10.1039/c5tc01238d
Abstract: Poly(3,4-ethylenedioxythiophene) (PEDOT) is a promising conductive polymer
for electrical applications, and increases in its conductivity, transparency,
stability, stiffness and strength have been explored. Herein, we demonstrate
a facile fabrication method for a PEDOT film that exhibits large anisotropic
conduction along in-plane directions. An aqueous solution of PEDOT added
with polystyrene sulfonate (PSS) was mixed with an insulating oxide nanosheet
based on montmorillonite (MMT) dispersed in aqueous media. Structural studies
demonstrated it to be a hybrid film with a lamellar-like assembly that
was structured with mono-layered sheets. In addition, an inhomogeneous
mixture of pristine MMT (insulating) and PEDOT-rich (conductive) lamellar
grains was proposed. The ratio between these two grains was controlled
by tuning the content of the PEDOT:PSS solution in the initial mixing process.
Increases in the content of PEDOT increased the electrical conductivity.
This dependence is explained by a percolation model with random arrangements
of PEDOT-rich conductive and insulating grains. The conductivity showed
large anisotropy between in-plane and out-of-plane measurements. The ratio
reached almost 105 and remained the same over a wide range of temperatures.
The lamellar structure of the PEDOT and nanosheets is ascribed to the large
anisotropy.