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Fabrication of Photovoltaic Devices using 1ovel Organic Polymer/1anostructure Blends David Black, Iulia Salaoru and Shashi Paul1 Emerging Technologies Research Centre, Room 00.43, Hawthorn Building, De Montfort University, The Gateway, Leicester, UK, LE1 9BH ABSTRACT Organic photovoltaic devices offer a potentially cheap source of electrical power due to the relative ease of processing compared to silicon devices. Over the last decade the efficiency of these devices has improved significantly and the best devices are currently have >6% power conversion efficiency and ~100% quantum efficiency. A novel blend of ferroelectric nanostructures, poly(3-hexylthiophene) (P3HT) and [6, 6]phenyl-C61-butyric acid methyl ester (PCBM) has been used to fabricate hybrid organic and inorganic photovoltaic devices. These devices comprise a glass substrate coated with indium tin oxide (ITO) and an layer of PEDOT:PSS to form the first electrode. The active layer was deposited by spin coating and finally metallic top contacts have been added by thermal evaporation. The devices were characterized using standard current-voltage (IV) measurements under illuminated and dark conditions using an AM1.5 solar simulator and a source-voltage device and the results indicate a difference in efficiency compared to similar devices fabricated at the same time without the novel nanostructures. Additional UV-Vis measurements were used to determine the absorption characteristics of the active layers. The initial results suggest an improvement in the absorption of light in the visible region and higher open circuit voltages and short circuit currents compared to P3HT/PCBM alone. I1TRODUCTIO1 Organic photovoltaic devices offer a potentially cheap source of electrical energy provided the inherent problems of efficiency and reliability can be overcome. With the exception of the dye sensitized devices such as the Graztel cell [1, 2] the current frontrunner devices are bulk heterojunction blends of Poly (3-Hexylthiophene) (P3HT) and [6, 6]-phenylC61-butyric acid methyl ester (PCBM). The best P3HT/PCBM heterojunction devices currently have power conversion efficiencies of around 6% and quantum efficiencies approaching 100% [3]. By adding ferroelectric nanoparticles to the P3HT/PCBM blends we have been able to demonstrate a relative increase in efficiency compared to P3HT/PCBM alone. The maximum efficiency of our devices does not yet equal that of the best devices produced at other institutions, but the principles are clearly demonstrated. We have previously demonstrated that adding ferroelectric nanoparticles such as barium titanate and strontium titanate to polymers can have a number of significant effects, firstly the permittivity of the material is increased [4] and secondly the photoconductivity of the material is increased [5]. Increasing the permittivity of the material has the effect of increasing the effective radius of the region in which excitons can dissociate, although the exact process by which this effect occurs has not yet been confirmed. In this