Fluorinated Porphyrin Electropolymer Films for Efficient and Stable Pseudocapacitive Energy Storage

Two porphyrin derivatives containing carbazole ( PPER‐CBZ ) and triphenylamine ( PPER‐TPA ) units were synthesized and electropolymerized to yield conducting films ( p‐PPER‐CBZ , p‐PPER‐TPA ) on glassy carbon (GC) and indium tin oxide (ITO) electrodes. Electrochemical quartz crystal microbalance measurements enabled real‐time monitoring of mass deposition during film growth. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses demonstrated that both p‐PPER‐CBZ and p‐PPER‐TPA films possess porous architectures, which contribute to their large electroactive areas. X‐ray photoelectron spectroscopy (XPS) measurements indicate that the fluorinated porphyrin cores remain unaltered in both films. Electrochemical and spectroelectrochemical analyses revealed multiple reversible redox processes involving all electroactive sites: the porphyrin macrocycle, tetraphenylbenzidine (TPB), or dicarbazole (DCBZ) dimers. Both electropolymers retained electroactivity over thousands of redox cycles without degradation or detachment from the substrate. Galvanostatic charge–discharge and electrochemical impedance measurements showed that p‐PPER‐TPA delivered the highest specific capacitance (310 F g ⁻¹ on GC) and the best cycling stability (90% retention after 3000 cycles). Using p‐PPER‐TPA as the active material, a quasi‐solid‐state asymmetric supercapacitor with a PEDOT counter‐electrode and gelled electrolyte was assembled. These results highlight the potential of structurally engineered porphyrin‐based electropolymers for stable, efficient pseudocapacitive energy storage.