Synthetic approach from polypyrrole nanotubes to nitrogen doped pyrolyzed carbon nanotubes for asymmetric supercapacitors

• Published in: Journal of power sources Vol. 308; pp. 158 - 165
• Main Authors: Dubal, Deepak P., Chodankar, Nilesh R., Caban-Huertas, Zahilia, Wolfart, Franciele, Vidotti, Marcio, Holze, Rudolf, Lokhande, Chandrakant D., Gomez-Romero, Pedro
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.03.2016
• Subjects: Asymmetry; Carbon nanotubes; Electrostatics; Energy density; Nanotubes; Polypyrroles; Supercapacitors; Texture
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2016.01.074

Pseudocapacitive materials are highly capable to achieve high energy density integrated with high power electrostatic capacitive materials. However, finding a suitable electrostatic capacitive material to integrate with pseudocapacitive material in order to achieve high energy density with good rate capability is still a challenge. Herein, we are providing a novel synthetic approach starting from the synthesis of polypyrrole nanotubes (PPy-NTs) and ending up at the carbonization of PPy-NTs to obtain N-doped carbon nanotubes (N-CNTs). With highly porous nature of PPy-NTs and great graphitic texture with copious heteroatom functionalities, N-CNTs significantly promoted the faradic pseudo-capacitors, demonstrating high single-electrode capacitance over 332 F/g(PPy-NTs) and 228 F/g(N-CNTs) in 1 M H2SO4 aqueous solution. Further, a novel asymmetric supercapacitor with PPy-NTs as positive and N-CNTs as negative electrode has been fabricated. This PPy-NTs//N-CNTs cell effectively provides high operation voltage (1.4 V) and hence high energy density over 28.95 W h/kg (0.41 mW h/cm3) with a high power density of 7.75 kW/kg (113 mW/cm3) and cyclic stability of 89.98% after 2000 cycles. •Synthesis of 1D PPy nanotubes.•Carbonization of PPy nanotubes to prepare N doped carbon nanotubes (N-CNTs).•Fabrication of asymmetric supercapacitor with PPy-NTs//N-CNTs.•High performance asymmetric device.