We investigated the ability of silver thin metal films to enhance photovoltaic conversion efficiency in blends of poly-3-hexylthiophene (P3HT) and methanofullerene [6,6]-phenyl C61-butyric acid methyl ester (PCBM). By varying the thickness of the silver films and developing a new fabrication routine that involves annealing for long periods of time at low temperatures, we were able to reproducibly enhance photoconversion in P3HT/PCBM devices. Photovoltaic conversion efficiency was monitored using internal photon to current conversion efficiency (IPCE) and current-voltage measurements. We observed that plasmonic materials were able to enhance the conversion efficiencies of organic, bulk heterojunction devices. The relationship between the surface plasmon resonance wavelength and overall device performance is also presented with IPCE data. These preliminary studies indicate that plasmonic enhancement in bulk heterojunction devices show promise to improve the viability of organic solar cells.

Date Published: 14 November 2007
PDF: 8 pages
Proc. SPIE 6656, Organic Photovoltaics VIII, 66561J (14 November 2007); doi: 10.1117/12.735480

Published in SPIE Proceedings Vol. 6656:
Organic Photovoltaics VIII
Zakya H. Kafafi; Paul A. Lane, Editor(s)