Stable ternary nanocomposites of Multi walled Carbon nanotube/ Polyaniline/ Hydroquinone: electrodes for Supercapacitors

Abstract

Multi-walled carbon nanotubes (MWCNTs) are widely used as supercapacitor electrode material. However, the specific capacitance of MWCNTs cannot achieve optimum value to facilitate required demand. Conducting polymers have been introduced to achieve optimum energy density and power density of supercapacitor electrode material. Conductive polymers are promising pseudo capacitive materials as they feature both good conductivity and high capacitance. Formation of composite using conductive polymers and carbon nanotubes is a proven technique in enhancing the material electroactivity. However, the cycling life and rate capability of PANI electrodes are unsatisfactory due to their large volume changes and slow redox reactions during charge-discharge processes. This work describes the effect of HQ adding on MWCNT/PANI composite prepared by insitu polymerization technique in order to increase the cyclic stability of MWCNT/PANI. PANI-HQ/MWCNT film offers intrinsic porous channels and promotes the transportation of charges and ions. Consequently, the PANI-HQ/MWCNT film electrode exhibits specific capacitance of 120 Fg-1 at a current density of 0.5A/g whereas PANI/MWCNT film exhibits 130 F/g. Although PANI-HQ/MWCNT film electrode exhibits less specific capacity than PANI/MWCNT they presents a good cycling stability with 94% of capacitance retention after 1000 cycles, much higher than that of PANI/MWCNT film (74%) electrodes. The excellent rate performance and cycling stability make it one of promising candidates for electrochemical energy storage