Restructured carbon aerogels and their electrochemical performances

Abstract

Restructured carbon aerogels (RCAs) were obtained by annealing carbon aerogels (CAs) in sodium melt at 800°C for 3 h and the differences in electrochemical performance between the resultant CAs and RCAs were studied. X-ray diffraction (XRD), Raman scattering spectra, gas physisorption (BET), transmission electron microscopy (TEM), and electrochemical impedance spectroscopy (EIS) were used to probe the structures of CAs and RCAs. The studies indicated that the amorphous carbon particles were rearranged in sodium melt, in which the surface area of the resultant RCAs was 48% larger than that of CAs. Two concentrated pore distributions were observed at the apertures of 2 and 4 nm in RCAs. The pore volume at apertures below 10 nm is 30% of the total volume in RCAs, which is 3 times as many as that in CAs. Electrochemical performances of both CAs and RCAs were investigated and the results indicate that the inner resistance of RCAs is only 45% of that in the sample of CAs. The results also indicate that RCAs display good performance in capacitance characteristics. © Editorial office of Acta Physico-Chimica Sinica.