Premium
Pseudocapacitance Effects for Enhancement of Capacitor Performance
Author(s) -
Lota G.,
Frackowiak E.
Publication year - 2010
Publication title -
fuel cells
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.485
H-Index - 69
eISSN - 1615-6854
pISSN - 1615-6846
DOI - 10.1002/fuce.201000032
Subject(s) - pseudocapacitance , supercapacitor , materials science , electrochemistry , melamine , carbon nanotube , electrolyte , electrode , capacitance , composite number , nitrogen , acetonitrile , activated carbon , chemical engineering , composite material , chemistry , organic chemistry , engineering , adsorption
We report on the pseudo‐capacitance induced by a nitrogen substituted in the carbon network composite prepared by a simple carbonisation (750 °C) of formaldehyde and melamine in the presence of carbon nanotubes. Nitrogen content in the composites varied from 7.4 to 21.7 wt.%. Such materials have a higher density than activated carbons, hence, they can supply better volumetric capacity. N‐rich composites show an excellent charge propagation at current loads from 500 mA g –1 to 50 A g –1 because of multiwalled nanotubes which play a conducting as well as a supporting role. The electrochemical performance of various composites was investigated in two‐ and three‐electrode cells using acidic (1 mol L –1 H 2 SO 4 ), alkaline (6 mol L –1 KOH), neutral (1 mol L –1 Na 2 SO 4 ) and organic electrolytes (1 mol L –1 TEABF 4 in acetonitrile). Organic and neutral medium is not adapted for N‐rich carbon electrodes of supercapacitor. The detailed electrochemical characterisation pointed out the differences of charge propagation of electrodes with the different polarity.