Young-Wan Ju

Adsorption of toluene on carbon nanofibers prepared by electrospinning

This paper reports the novel results of activated carbon nanofibers (ACNF) used to improve the toluene adsorption capacity. The ACNF was prepared by stabilization, carbonization and activation after electrospinning the polymer solution of polyacrylonitrile (PAN) in N, N-dimethylformamide. The average diameter of the ACNF was approximately 300 nm, ranging from 200 to 500 nm. The toluene adsorption capacity of ACNF10 activated at 1000 degrees C increased to 65 g-toluene/100 g-ACNF. This was attributed to the high specific surface area (1403 m(2)/g), large micropore volume (0.505 cm(3)/g), and narrow average pore diameter (6.0 A). The oxygen to carbon ratio (O/C ratio) in ACNF10 was 1.8%. This O/C ratio appears to induce a higher toluene adsorption capacity, which originates from a non-polar interaction between the ACNF surface and toluene. In conclusion, the electrospun ACNF prepared in this study promotes the adsorption of toluene through the high specific surface area, large pore volume, narrow pore diameter and low O/C ratio.

A Hydrous Ruthenium Oxide-Carbon Nanofibers Composite Electrodes Prepared by Electrospinning

Ruthenium-embedded carbon nanofibers were prepared by the processes of stabilization, carbonation, and activation after electrospinning a composite solution of ruthenium(III) acetylacetonate and polyacrylonitrile in N,N-dimethylformamide. When Ru particles were embedded in the carbon nanofibers, the average pore diameter increased from 2.0 to 2.5 nm. The Ru particles were embedded randomly within the carbon fibers, and the size distribution of the Ru particles ranged from 2 to 15 nm. The specific capacitance of the carbon nanofiber without the Ru loading was 140 F/g, while that of 7.31 wt % Ru-carbon nanofibers increased to 280% as 391 F/g. This was attributed to the synergistic effect of electric double-layer capacitance as a result of the expansion of the average pore diameter as well as the pseudocapacitance by the well-dispersed Ru particles.

Electrochemical Performance of Electrospun ACNF Electrodes Using Polymer Blend

The aim of this work is to fabricate the electrospun ACNF electrodes with highly electrochemical performance using polymer blend of polyacrilonitrile (PAN) – cellulose acetate (CA) for supercapacitors. The blended ACNFs have a lager specific surface area and an average pore diameter compared to non-blended ACNFs. That was occurred by formation of valley due to difference of pyrolysis between PAN and CA. The blended ACNFs also had higher electrical conductivity than to nonblended ACNFs. The specific capacitances of the prepared webs ranged from 141 to 221 F/g, depending on the CA blending ratio. The 30 wt.% CA blended ACNFs exhibited the highest capacitance as 221 F/g. This was attributed to the increase of specific surface area, pore diameter and electrical conductivity.