Preparation and characterization of binder-free electrodes based on PEDOT and perovskites type La (1-x) Sr x MnO 3 for use in supercapacitors

Positive electrodes for pseudocapacitators are commonly assembled with a pseudocapacitive material, an electrically conductive material, and a binder. Generally, binders present high electrical resistance, shown as losses in the electrode efficiency. Therefore, there is a need to develop new electrode materials with better electrical conduction properties. This paper proposes to replace the classical electrical binder-conductor system, in La0.7Sr0.3MnO3 (LSMO) and LaMnO3 (LMO) pseudocapacitive electrodes, with the Poly(3,4-ethylenedioxythiophene) PEDOT, a polymer with the double function of conductivity and binding. In this work, different LSMO and LMO electrode materials with PEDOT were synthesized by cyclic voltammetry at different ratios (5, 10, 15, 20, 30% wt ) of pseudocapacitive material with respect to the conductive polymer. The LSMO/PEDOT type materials with a ratio of 15% wt showed the highest capacitance with a value around 116 F/g. Also, a high stability material was obtained as shown in charge–discharge curves, with efficiencies of 94% at 272 mA/s∙g discharge current cycles. Additionally, a cyclability test was performed with 5000 cycles showing a coulombic efficiency of 87% and only 10% of capacitance loss.