INVESTIGATION OF CARBON NANOFIBERS AS COUNTER ELECTRODES IN DYE SENSITIZED SOLAR CELLS

Carbon nanofibers (CNF) can represent a possible alternative to platinum and other graphitic carbonaceous materials for Dye-Sensitized Solar Cell (DSSC) counter electrodes, both from the economic point of view and for what concerns the performance. Carbon nanofibers obtained under different synthesis temperatures were physico-chemically characterized and tested as counter electrode by voltamperometric polarization and impedance measurements under AM 1.5 illumination. The morphological and structural characterization permitted to observe a decrease in surface area and an increase of the crystallinity with the CNF growth temperature. The morphology of these nanofibers is clearly one-dimensional from the electronic microscopy observation, which corresponds to a high electronic conductivity. The best performance as counter electrode in DSSC was found with the CNF characterized by a high surface area and thin nanofilaments.