Fabrication of Tiron-doped polypyrrole/MWCNT composite electrodes with high mass loading and enhanced performance for supercapacitors

In this study, the aromatic sulfonate compound Tiron with high charge to mass ratio is used as an anionic dopant for synthesis of polypyrrole (PPy). The fabricated PPy is investigated for electrochemical supercapacitor (ES) application. Testing results show that Tiron allows reduced PPy agglomeration, smaller particle size and improved charge storage properties of PPy. High capacitance and improved capacitive retention at high scan rates are achieved by the fabrication of PPy/multiwalled carbon nanotube (MWCNT) composite electrode using safranin (SAF) as a co-dispersant. The Tiron-doped PPy electrode shows the highest capacitance of 7.8 F cm⁻² with a mass of 27 mg cm⁻². The Tiron-doped PPy/MWCNT composite electrode shows good capacitance retention with a capacitance of 1.0 F cm⁻² at the scan rate of 100 mV s⁻¹. Symmetric supercapacitor cells are fabricated using PPy based active materials. An energy density of 0.36 mWh cm⁻² is achieved. The energy/power density and capacitance retention of the Tiron-doped PPy/MWCNT ES is significantly improved in comparison with PPy-based ES, prepared without Tiron or MWCNT. The Tiron-doped PPy/MWCNT symmetric supercapacitor presents good cycling performance with 91.4% capacitance retention after 1000 charge–discharge cycles. The PPy/MWCNT composites, prepared using Tiron and SAF co-dispersant, are promising electrodes for ES. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42376.