ºÚÁÏÍø

Abstract

Recently, electrochemical capacitors have been carried out with emphasis on the development of hybrid electroactive electrode materials, based on metal oxide, carbon materials and conducting polymers. The hybrid NiCo2O4 modified carbon fiber paper (NiCo2O4/CFP) composites with different electrodeposited times of polypyrrole (PPy) layers were prepared by two-step process. At first, NiCo2O4 was prepared by low temperature hydrothemal method. Secondly, PPy layer were coated onto the NiCo2O4/CFP composites by using electrochemical deposition method. The potential sweeping between –0.2 to 1.0 V at a scan rate of 50 mV/s was performed for various potential sweeping cycles (0, 5, 10, 15 and 20) in 0.5 M KCl solution in the presence of pyrrole monomer. SEM images clearly indicated that the NiCo2O4 nanoneedles were uniformly grown over the CFP. Further, PPy layer was uniformly deposited over the NiCo2O4/CFP composites. In the present work, we have fabricated various hybrid NiCo2O4/CFP composite electrodes with different electrodeposited PPy layers, and the effects of electrodeposited PPy layer were investigated. The as-prepared NiCo2O4/CFP composite electrodes with PPy layer electrodeposited for 15 cycles (NiCo2O4-PPy15/CFP) showed good electrochemical performance. Further, NiCo2O4-PPy/CFP composite electrode was successfully utilized for solid-state high performance supercapacitor applications. It showed high capacitance value with high energy and power density as well as high rate capability, which were evaluated from galvanostatic charge-discharge and electrochemical impedance spectroscopy.

Biography

E-mail: Taehoon222@naver.com