Increased performance of single walled carbon nanotube photovoltaic cells through the addition of dibenzo[b,def]chrysene derivative

Vertically aligned arrays of single walled carbon nanotubes (SWNTs) were chemically attached to an optically transparent electrode of fluorine doped tin oxide (FTO) for use as a working electrode in a photoelectrochemical solar cell. 7,14-Bis[2-[tris(1-methylethyl)silyl]ethynyl]dibenzo[b,def]chrysene (TIPS-DBC) layers were deposited onto the SWNT/FTO electrodes via spin coating. The photovoltaic properties of these new TIPS-DBC/SWNT/FTO electrodes were then investigated. The presence of the additional TIPS-DBC layer was found to increase the open circuit voltage, short circuit current density and power conversion efficiency of the cells compared to those cells made using nanotube only electrodes. In addition, the spin speed at which the TIPS-DBC layer was deposited was found to have an effect on the photovoltaic performance of the cells. These results show much promise for the further development of photovoltaics in which the photoactive elements are carbon based, rather than transition metal based.