1 research outputs found
Direct Writing and Characterization of Three-Dimensional Conducting Polymer PEDOT Arrays
Direct writing is
an effective and versatile technique for three-dimensional
(3D) fabrication of conducting polymer (CP) structures. It is precisely
localized and highly controllable, thus providing great opportunities
for incorporating CPs into microelectronic array devices. Herein we
demonstrate 3D writing and characterization of polyÂ(3,4-ethylenedioxythiophene)-polystyrenesulfonate
(PEDOT:PSS) pillars in an array format, by using an in-house-constructed
variant of scanning ion conductance microscopy (SICM). CP pillars
with different aspect ratios were successfully fabricated by optimizing
the writing parameters: pulling speed, pulling time, concentration
of the polymer solution, and the micropipette tip diameter. Especially,
super high aspect ratio pillars of around 7 μm in diameter and
5000 μm in height were fabricated, indicating a good capability
of this direct writing technique. Additions of an organic solvent
and a cross-linking agent contribute to a significantly enhanced water
stability of the pillars, critical if the arrays were to be used in
biologically relevant applications. Surface morphologies and structural
analysis of CP pillars were characterized by scanning electron microscopy
and Raman spectroscopy, respectively. Electrochemical properties of
the individual pillars of different heights were examined by cyclic
voltammetry using a double-barrel micropipette as an electrochemical
cell. Exceptional mechanical properties of the pillars, such as high
flexibility and robustness, were observed when bent by applying a
force. The 3D pillar arrays are expected to provide versatile substrates
for functionalized and integrated biological sensing and electrically
addressable array devices