화학공학소재연구정보센터
Electrochimica Acta, Vol.245, 531-538, 2017
Impact of binder concentration and pressure on performance of symmetric CNFs based supercapacitors
This paper discussed in details the impact of binder polyvynilidene fluoride (PVDF) concentrations (5, 10 and 20 wt%) and pressures (similar to 382 similar to 891 similar to 1783 and similar to 2547 MPa) for the fabrication of electrodes based on Carbon nanofibers (CNFs) for supercapcitors. The surface area, pore size distribution and morphology were characterized by Brunauer-Emmett-Teller (BET) method and SEM. The decrease in specific surface area was about 31% and pore volume 14.6% with increase in PVDF concentration from 5 to 20 wt% at similar to 891 MPa pressure. The assembled electrodes were tested with two electrode system in aqueous electrolyte. The specific capacitance was 80 F/g for lowest concentration of PVDF (5 wt%) and decreased about 28.3% with increase concentrations at same pressure similar to 891 MPa. In comparing the effect of pressure on specific capacitance, it increases about 38% for (PVDF, 10 wt%; pressure similar to 1783 MPa) from (PVDF, 10 wt %; pressure similar to 891 MPa); their corresponding power density 24502 W/kg at energy density of 6.8 Wh/Kg and 19886 W/kg at energy density energy of 3.8 Wh/kg. ESR values increase from 0.3 to 1.9 V with increase in PVDF concentration and decrease again to 0.5 V with increase in pressure. The results show optimal conditions are 10 wt% of PVDF and higher pressure of similar to 891 MPa. (C) 2017 Elsevier Ltd. All rights reserved.