Evaporative successive ionic layer adsorption and reaction polymerization of PEDOT: a simple and cost effective technique for binder free supercapacitor electrodes

The present article describes the development of nanostructured poly(3, 4-ethylenedioxythiophene) (PEDOT) thin film supercapacitor electrodes via conventional solution based inexpensive synthetic approach. Here a novel and simple evaporative successive ionic layer adsorption and reaction (ESILAR) method has been employed to polymerize binderless PEDOT thin films on graphite electrode using ferric chloride (FeCl₃) oxidant. This method yields PEDOT thin films of good electrochemical performance with high active material loading (∼2.7–8 mg cm⁻² with specific capacitance in the range of ∼129–165 F g⁻¹) and exhibits a high specific capacitance of 165 F g⁻¹ for 5.3 mg cm⁻² PEDOT thin film coated electrode in 1 M H₂SO₄ electrolyte. The effects of various number of ESILAR coating cycles were investigated in terms of the structural, morphlogical and electrochemical properties of PEDOT thin film nanostructures. The PEDOT nanostructures deposit as a straightforward freestanding suface structures were easily processable into a supercapacitor electrodes characterized by excellent cycling stability of ∼80–90% of its initial capacitance retaining after 4000 cycles even free from conductive additives and binders. This method provides a useful orientation on the facile and efficient deposition method of PEDOT thin films applicable for the electrochemical energy storage devices.