PLASMA TREATMENT OF ELECTROPHORETICALLY DEPOSITED CARBON NANOTUBE TRANSPARENT ANODES FOR THE DEVELOPMENT OF ORGANIC SOLAR CELLS D. Bagnis1, L. Valentini1, R. Cagnoli2, F. Mengoni1, A. Mucci2, L. Schenetti2, J.M. Kenny1 1Dip. di Ingegneria Civile e Ambientale, Università di Perugia, NIPLAB-INSTM UdR Perugia, Pentima Bassa 21, Terni, 05100 (TR) - ITALY 2Dip. di Chimica, Università di Modena e Reggio Emilia, Via Campi, 183, Modena, 41100 (MO) - ITALY PD16

Our Device Architecture Fluorine Doped Tin Oxide (FTO) (Tec Glass 15®, surface resistance 14/sq) was immersed into a nanotube suspension of CH3CN and kept parallel to an opposite gold electrode (2 cm apart). A dc voltage of +4 V was applied to the FTO electrode maintaining the gold plate at ground the deposition of carbon nanotube films was observed on the positive electrode. After electrodeposition, the e-SWCNT thin films were plasma treated in oxygen or CF4 atmosphere. The photosensitive PTCOOH film was deposited by drop-casting the THF solution of the polymer. Poly[7-(thien-3-ylsulfanyl)heptanoicacid]-co-thiophene PD16

Plasma Induced Fragmentation of Carbon Nanotube FESEM images of three different hybrid anodes: (a) e-SWCNT/FTO, (b) CF4 plasma treated e-SWCNT/FTO and (c) Oxygen plasma treated e-SWCNT/FTO Transmittance in the visible and near-infrared regions for e-SWCNT/FTO, CF4 plasma treated e-SWCNT/FTO and Oxygen plasma treated e-SWCNT/FTO. PD16

Height topography (left pictures) and phase topography (right pictures) AFM images (8X8 mm2) of PTCOOH / FTO. PTCOOH / CF4 plasma treated e-SWCNT / FTO. PTCOOH / oxygen plasma treated e-SWCNT / FTO. PD16

PD16 Samples VOC [V] JSC [mA/cm2] FF h [%] 0.48 0.045 0.25 0.01 0.75 Glass Al PTCOOH e-SWCNTs FTO Active Area AM 1.5G (76 mW/cm2) Samples VOC [V] JSC [mA/cm2] FF h [%] PTCOOH / FTO 0.48 0.045 0.25 0.01 PTCOOH / e-SWNTs / FTO 0.75 0.23 0.22 0.05 J–V curve under illumination for the organic solar cell prepared with oxygen plasma treated e-SWCNTs/FTO anode. J–V curve under illumination for the organic solar cell prepared with neat FTO anode. PD16

CONCLUDING REMARKS It was found that a surface plasma treatment of the SWCNT anodes leads to the formation of an absorptive nanostructure which collects more charges from the polymer than that of the neat FTO in contact with the polymer. We have demonstrated that PTCOOH can be drop-casted onto a SWCNT electrode thin film to form a new type of functional nanostructure. The excellent conductivity and the semiconducting behaviour of the nanocomposite are envisaged to make it very useful for the development of electronic micro-devices for practical applications. We propose the use of electrophoretically deposited SWCNT thin films as anodes in polymer solar cells. PD16