Double‐decker lutetium and europium phthalocyanine composites with reduced graphene oxide as supercapacitor electrode materials

Abstract

Double‐decker phthalocyanines were synthesized by a classical method with phthalonitrile and lanthanide metal salts, europium and lutetium acetate. Non-covalent double-decker phthalocyanine-reduced graphene oxide (MPc2/rGO) composites were then prepared by simple sonication method. All the phthalocyanines were peripheral tetrasubstituted 5-(3-pyridyl)-1,3,4-oxadiazole. Following spectroscopic and morphological characterisation, fabricated composites were subjected to detailed electrochemical analysis. EuPc2/rGO and LuPc2/rGO composite electrodes showed specific capacitance values of 115 F/g and 86 F/g, respectively. Coulombic efficiency values for those materials were determined as 85% and 74%, respectively, at a significant current density of 5 A/g. Following 5000 cycles, EuPc2/rGO and LuPc2/rGO electrodes retained 93% and 99% of their initial capacitance, respectively. These results demonstrated the significant electrochemical performance of double-decker phthalocyanines and can be certainly extended to other metal salts or other composite formers with double-decker phthalocyanines.