Design and Characterization of Liquid Crystal-Graphite Composite Electrodes

Thermotropic ionic liquid crystals (ILCs), 1,1'-dialky1-4,4'-bipyridinium bis(triflimide)s have been used as binders to fabricate new carbon composite electrodes. ILC compounds possess an ordered molecular orientation, and upon mixing with graphite, ILCs retain their liquid crystal characteristics and thus their ordered arrangement. The electrochemical performances of these composite electrodes were evaluated by using different electrochemical probes. The resulting electrodes offer high electrochemical reactivity, low background current, improved signal-to-noise ratio, greater stability, excellent mechanical strength, and very good antifouling effects. It is believed that the higher conductivity of ILCs as well as the ordered orientation of these thermotropic ILCs which cause an increase in the edge-plane sites of these composite electrodes are responsible for the promotion of their electrocatalytic activities and antifouling effects. Such characteristics make these composite electrodes ideal for use in different electrochemical and biosensing applications.