Effect of surface phosphorus functionalities of activated carbons containing oxygen and nitrogen on electrochemical capacitance.
Micro/mesoporous activated carbons containing oxygen and phosphorus heteroatoms were modified by incorporation of nitrogen using melamine and urea precursors. The surface chemistry was analyzed by the means of elemental analysis, XPS, and (31)P MAS NMR. The results indicate that upon the incorporation of nitrogen at high temperatures not only new species involving carbon/nitrogen/oxygen are formed but also the phosphorous environment is significantly altered. Both urea and melamine precursors have similar effects on formation of P-N and P-C bonds. These compounds, although present in small but measurable quantities seem to affect the performance of carbons in electrochemical capacitors. With an increase in the heterogeneity of phosphorus containing species and with a decrease in the content pyrophosphates the capacitance increases and the retention ratio of the capacitor is improved.
Hulicova-Jurcakova
Denisa
D
The University of Queensland, ARC Centre of Excellence for Functional Nanomaterials, Australian Institute for Bioengineering and Nanotechnology, Corner College and Cooper Roads, St. Lucia, 4072 QLD, Australia.
Seredych
Mykola
M
Lu
Gao Qing
GQ
Kodiweera
N K A C
NK
Stallworth
Phillip E
PE
Greenbaum
Steven
S
Bandosz
Teresa J
TJ