| Photovoltaic properties of functionalised single-walled carbon nanotubes (SWNT)-conjugated polymer, poly(3-octylthiophene) (P3OT), blend composites are reported. Devices were fabricated by spin cast from the solution of composite onto ITO coated glass. The carbon nanotubes were functionalised in order to increase their solubility and dispersion. Diodes (ITO/PEDOT:PSS/P3OT-SWNTs/Al) with low nanotube concentration (1%) show photovoltaic behaviour, with a short circuit current of 0.25 mA/cm2, an open circuit voltage of 0.75 V and a fill factor of 0.48, resulting in an AM 1.5 power conversion efficiency of 0.1%. It is proposed that the photovoltaic response of the device is based on the introduction of internal polymer-nanotube junctions within the polymer matrix, which due to a photoinduced electron transfer from the polymer to the nanotube contribute to enhanced charge separation and collection. It is shown that the carbon nanotubes represent an alternative class of electron acceptor materials for applications in polymeric photovoltaics |
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