5 research outputs found
Supercapacitance from cellulose and carbon nanotube nanocomposite fibers
Copyright © 2013 American Chemical SocietyACS AuthorChoice open access articleMultiwalled carbon nanotube (MWNT)/cellulose composite nanofibers have been prepared by electrospinning a MWNT/cellulose acetate blend solution followed by deacetylation. These composite nanofibers were then used as precursors for carbon nanofibers (CNFs). The effect of nanotubes on the stabilization of the precursor and microstructure of the resultant CNFs were investigated using thermogravimetric analysis, transmission electron microscopy and Raman spectroscopy. It is demonstrated that the incorporated MWNTs reduce the activation energy of the oxidative stabilization of cellulose nanofibers from 230 to 180 kJ molâ1. They also increase the crystallite size, structural order, and electrical conductivity of the activated CNFs (ACNFs). The surface area of the ACNFs increased upon addition of nanotubes which protrude from the fiber leading to a rougher surface. The ACNFs were used as the electrodes of a supercapacitor. The electrochemical capacitance of the ACNF derived from pure cellulose nanofibers is demonstrated to be 105 F gâ1 at a current density of 10 A gâ1, which increases to 145 F gâ1 upon the addition of 6% of MWNTs.The authors would like to thank the [Engineering and Physical Sciences Research Council] EPSRC (EP/F036914/1 and EP/I023879/1), Guangdong and Shenzhen Innovative Research Team Program (No. 2011D052,KYPT20121228160843692), National Natural Science Foundation of China (Grant No. 21201175), R&D Funds for basic Research Program of Shenzhen (Grant No. JCYJ20120615140007998), and the Universities of Exeter and Manchester for funding this research
Supercapacitance from Cellulose and Carbon Nanotube Nanocomposite Fibers
Multiwalled carbon nanotube (MWNT)/cellulose
composite nanofibers have been prepared by electrospinning a MWNT/cellulose
acetate blend solution followed by deacetylation. These composite
nanofibers were then used as precursors for carbon nanofibers (CNFs).
The effect of nanotubes on the stabilization of the precursor and
microstructure of the resultant CNFs were investigated using thermogravimetric
analysis, transmission electron microscopy and Raman spectroscopy.
It is demonstrated that the incorporated MWNTs reduce the activation
energy of the oxidative stabilization of cellulose nanofibers from
âŒ230
to âŒ180 kJ mol<sup>â1</sup>. They also increase the
crystallite size, structural order, and electrical conductivity of
the activated CNFs (ACNFs). The surface area of the ACNFs increased
upon addition of nanotubes which protrude from the fiber leading to
a rougher surface. The ACNFs were used as the electrodes of a supercapacitor.
The electrochemical capacitance of the ACNF derived from pure cellulose
nanofibers is demonstrated to be 105 F g<sup>â1</sup> at a
current density of 10 A g<sup>â1</sup>, which increases to
145 F g<sup>â1</sup> upon the addition of 6% of MWNTs