The influence of urea on composition, microstructure and electrochemical properties of nitrogen-enriched carbon based on polyvinylpyrrolidone/melamine formaldehyde resin
Abstract
Purpose
The purpose of this paper is to develop porous nitrogen-enriched carbon (NC-U) with high nitrogen concentration and high specific capacitance (Cpe) as the electrode material for supercapacitors.
Design/methodology/approach
NC-U was obtained by carbonization of polyvinylpyrrolidone/melamine formaldehyde resin (PVP/MF) with different contents of urea. In comparison, NC-K was also prepared by the KOH activation method. A series of asymmetric supercapacitors with NC as a negative electrode was assembled. The composition, microstructure and electrochemical properties of NC and their supercapacitors were studied.
Findings
The results show that NC-U shows irregular particles with a porous honeycomb structure. High Cpe was obtained for urea-treated NC-U because of the improvement of nitrogen, conductivity and specific surface area (S BET ). NC-U50 with 13.15 per cent at nitrogen has the highest Cpe of 148.53 F/g because of the highest concentration of N-6 and N-5. NC-K with higher S BET has lower Cpe than NC-U50 because of its lower nitrogen concentration. When the specific power of the supercapacitor with NC-U50 as a negative electrode is 1,565.56 W/kg, its specific energy is still 4.35 Wh/kg. There is only 5.9 per cent decay in Cpe over 1,000 cycles.
Research limitations/implications
NC-U is a suitable electrode material for supercapacitors, which can be used in the field of electric vehicles to solve the problems of energy shortage and environmental pollutions.
Originality/value
Porous NC-U based on PVP/MF/urea composites with high nitrogen concentration and Cpe is novel, and it owns good electrochemical properties.
Keywords
Acknowledgements
The authors gratefully acknowledge the financial assistance of Natural Science Foundation Committee of China (Grant Number 21206034, 21372067, 51373049), and Outstanding Youth Science Foundation Committee of Heilongjiang University (Grant Number JCL201202).
Citation
Li, Q., Du, J., Zhang, X., Qin, C., Jin, Z. and Bai, X. (2015), "The influence of urea on composition, microstructure and electrochemical properties of nitrogen-enriched carbon based on polyvinylpyrrolidone/melamine formaldehyde resin", Pigment & Resin Technology, Vol. 44 No. 5, pp. 257-265. https://doi.org/10.1108/PRT-02-2015-0017
Publisher
:Emerald Group Publishing Limited
Copyright © 2015, Emerald Group Publishing Limited