Composites Based on Poly(Diphenylamine-2-carboxylic Acid) and Highly Porous Carbon for Flexible Electrodes of Supercapacitors

Electrochemical behavior of hybrid electrodes with electroactive coatings based on activated IR-pyrolyzed polyacrylonitrile as well as hybrid polymer-carbon composites with activated IR-pyrolyzed polyacrylonitrile (porous N-doped carbon component) and poly(diphenylamine-2-carboxylic acid) (polymer component) has been investigated for the first time in a lithium-organic electrolyte (1 M LiClO₄ in propylene carbonate). Electrochemical behavior of the coatings has been investigated at a smooth glass carbon surface and at flexible strips of anodized graphite foil with developed porous loosened surface. Specific electrochemical capacity of the hybrid electrodes has been found dependent on the conditions of the composite coating synthesis. The influence of heat treatment on the electrochemical behavior of the activated IR-pyrolyzed polyacrylonitrile–poly(diphenylamine-2-carboxylic acid) composites has been investigated. Heat-resistant electroactive coatings have been obtained for the first time under conditions of IR heating of the IR-pyrolyzed polyacrylonitrile–poly(diphenylamine-2-carboxylic acid) composites, specific capacity of which in a lithium aprotic electrolyte has been 0.107–0.114 F/cm², only ~17% less than this for the starting composites at anodized graphite foil support, due to compaction of the electroactive layers hindering the electrolyte transport.