FABRICATION, CHARACTERIZATION AND BUFFER LAYER MODIFICATION OF P3HT: PCBM BASED ORGANIC SOLAR CELLS

Abstract

Concerns about Global Warming and diminishing fossil fuel reserves have accelerated the search for low cost sources of renewable energy. Organic photovoltaics (OPVs) could be one such source. This thesis took the first step towards that goal by developing a process to synthesize and characterize inverted and normal poly (3-hexylthiophene) (P3HT), [6,6]-phenyl-C61 butyric acid methyl ester (PC60BM) solar cells. Although detrimental to the stability of the cells, ambient synthesis replicated the conditions required for large-scale, industrial production. Performance and stability were evaluated for each type of OPV. The most efficient normal cell had a power conversion efficiency of 0.308 %, a fill factor of 32.8%, and a VOC of up to 0.557 V. The buffer layer used was replaced by new transition oxides (MoO3) due to the limitations faced by the traditional layers. Then, some new inverted structures were investigated with efficiencies as high as 1.71 %, with a fill factor of 58.2 % and a VOC of 0.606 V. The inverted cells were much more stable than the normal cells. Some cells with new polymers need optimization but they did give some promising results.