9-13 July 2012
Africa/Johannesburg timezone
Home > Timetable > Session details > Contribution details
PDF | XML | iCal

Thickness and Solvent influence on the photo-active layer in Organic photovoltaic devices

Presented by Ms. Pontsho Sylvia MBULE on 10 Jul 2012 from 17:30 to 19:30
Type: Poster Presentation
Session: Poster Session
Track: Track A - Division for Condensed Matter Physics and Materials


Abstract To date, organic photovoltaic (OPV) devices made from a blend of conjugated polymers such as poly(3-hexylthiophene-2,5-diyl), (P3HT) and fullerene derivative [6,6]-phenyl C60 butyric acid methyl ester (PCBM) have attracted much attention because of their promising improvement of power conversion efficiencies. In this study, we investigate the effect of solvent on the fabrication of photo-active layers (P3HT:PCBM) in OPV devices. Dissolving the photo-active materials in Chloroform, 1,2 dichlorobenzene and chlorobenzene solvents, optical absorption of blended films was evaluated and thin films made from chloroform showed intense absorption compared to 1,2-dichlorobenzene and chlorobenzene. Surface profile determined by Alpha-step IQ showed thin films of thickness of about 138.8 nm (chloroform), 56,1 nm(1,2-dichlorobenzene) and 75.2 nm (chlorobenzene). The OPV devices comprised of an active layer P3HT:PCBM blend, sandwiched between a transparent conductive oxide (ITO) coated glass as a anode and a top metal layer (Al) as an cathode giving the device configuration of ITO|PEDOT:PSS|P3HT:PCBM|Al. The current density-voltage (J-V) characteristics measured with a solar simulator calibrated with a silicon-based reference cell providing an AM 1.5G spectra at 100mW/cm2 and external quantum efficiencies (EQE) measured using incident photo-to-current efficiency measurement system are discussed. The maximum power conversion efficiency of ~ 3.45 % was obtained from the device fabricated using chloroform as a solvent, while the power conversion efficiencies of ~2.94 % and ~2.86 % were obtained when chlorobenzene and 1,2-dichlorobenzene were used, respectively, as solvents.






Prof. O.M Ntwaeaborwa




Location: IT Building

Primary authors