Electropolymerized porphyrin films as active materials in organic supercapacitors. A study of the effect of different central metals

•Four porphyrin monomers were electropolymerized over conductive electrodes.•The electroactive polymers underwent reversible redox processes that generate pseudocapacitance.•Electrochromic behaviors were observed for the polymeric films.•The porphyrin films showed very good performances as supercapacitive materials.