A new kind of supercapacitor electrodes prepared by carbonisation of PAN/Carbon nanotubes composites

摘要

Supercapacitor electrodes have been prepared by one-step carbonisation of multiwalled carbon nanotubes (CNTs)/polyacrylonitrile (PAN) blends in neutral atmosphere. The capacitance values were estimated by galvanostatic and voltammetry measurements in acidic medium. The capacitance of the composites (50-110 F/g) definitively exceeded that of the single components, respectively a few F/g for carbonised PAN and ca. 20 F/g for the pristine nanotubes. Such a result is explained by the synergy of two effects related with the simultaneous presence of the two components. The strongly entangled network of CNTs reinforces the composite, preventing an important shrinkage during the carbonisation process. On the other hand, the composite matrix is auto-activated by the decomposition gases which evolve in the bulk of the carbonised polymer. The performance of the composite is discussed depending whether oxygen stabilisation was performed or not. This very simple and new process of electrodes production is very attractive; moreover the presence of nanotubes is very profitable for a good electronic conductivity of the electrodes.