Improving the electrochemical performance by sulfonation of polyaniline-graphene-silica composite for high performance supercapacitor

ABSTRACT

In this work, to increase the specific capacitance and energy density of reduced graphene oxide–silica composite (RGO-SiO₂), pseudocapacitive behaviour of polyaniline is introduced to RGO-SiO₂(PANI-RGO-SiO₂) and further improved by sulfonating the polyaniline system (SPANI-RGO-SiO₂). Formation of SPANI-RGO-SiO₂ is confirmed from IR and XRD analyses. SPANI-RGO-SiO₂ shows nanorods morphology with less crystalline nature. The specific capacitance of RGO-SiO₂ is increases from 24 to 780 F g⁻¹ with sulfonation of polyaniline in RGO-SiO₂. Retention in the specific capacitance value of SPANI-RGO-SiO₂ is 85% with that of its original value of 780 F g⁻¹ with coulombic efficiency (96–99%).

GRAPHICAL ABSTRACT

KEYWORDS:

• Graphene
• polyaniline
• sulfonation
• supercapacitor
• ternary composite