Polyaniline binder for functionalized acetylene black: A hybrid material for supercapacitor

• Functionalized acetylene black doped polyaniline as hybrid material for supercapacitor.
• Single hybrid material acts as combination of EDLC and pseudocapacitor.
• Small quantity of PANI induces binding property for FAB in PANI-FAB.
• High stable electrode material with low charge-transfer resistance and time constant.

Polyaniline-doped with functionalized acetylene black material has been successfully synthesized and used as an electrode material in supercapacitor, wherein, this material contributes both pseudocapacitive (PC) and electrical double layer capacitive (EDLC) behavior. Functionalization of acetylene black (AB) has been carried out and used as dopant for THF soluble polyaniline base (PANI) to prepare PANI-functionalized acetylene black (PANI-FAB). Formation of FAB and PANI-FAB was confirmed with the help of FT-IR and XPS study. Functionalization of AB results in agglomerated FAB and doping with PANI results in agglomerated fibrous PANI-FAB, as compared to fibrous AB. High thermal stability of AB decreases on functionalization and again slightly increases for PANI-FAB. Functionalization of AB also results good bonding effect with PANI, where PANI acts as both PC and binder, instead of the higher amounts of binder (PVdF > 30 wt%) that are normally needed to hold AB. Electrochemical studies of FAB and PANI-FAB materials were carried out by cyclic voltammetric and electrochemical impedance spectroscopic methods. PANI-FAB supercapacitor cell shows capacitance of 132 Fg−1 for 0.3 Ag−1 current density with very low charge-transfer resistance and low time constant.