Electrochimica Acta, Vol.53, No.23, 6722-6731, 2008
Preparation and characterization of poly[Ni(salen)(crown receptor)]/multi-walled carbon nanotube composite films
Nanocomposite films comprising walled carbon nanotubes (MWCNTs) embedded within poly [Ni(3-Mesalophen-b15-c5)] were deposited on Pt and ITO electrode surfaces by the potentiodynamic polyrnerisation of [Ni(3-Mesalophen-b15-c5)] from solutions containing dispersed MWCNTs. Composites incorporating carbon nanotubes subject to a range of oxidising pre-treatments were compared with those incorporating untreated carbon nanotubes and with the pure polymer. In both cases the use CH3CN and CH2Cl2 as fabrication and characterization media were explored. Films were characterized by voltammetry. electrochemical impedance spectroscopy and scanning electron microscope (SEM). The coating of the carbon nanotubes with polymer varied significantly with pre-treatment and solvent medium; this influenced the final composite morphology and electrical properties. Performance enhancement of the polymer component by the presence of the carbon nanotubes was manifested through the ability to store charge and the ease with which this Could he accomplished; these were parameterized via increased redox capacitance and decreased charge-transfer resistance, respectively. Correlation of impedance parameters with SEM images provided a morphological rationale for composite electrical properties.
Keywords:electroactive polymers;multi-walled carbon nanotubes;composite film morphology;SEM;electrochemical impedance