In this paper, we described an engineered enhancement of optical absorption in an organic photovoltaic cell via the excitation of surface plasmon resonance (SPR) in spherical Au nanoparticles deposited on a device surface. We deposited gold nanoparticles with 5 nm in diameter on ITO (indium tin oxide) glass substrates and then coated poly (styrenesulfonate) / poly (2,3-dihydro-thieno-1,4-dioxin) (PEDOT) which can reduce the work function of metal atoms and poly {2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene} (MEHPPV) with Fullerene(C₆₀) mixtures that work as p-type and n-type organic semiconductors, respectively. By using Mie theory simulation, we could predict SPR resonance peak of gold nanoparticles and we assume the enhancement in electromagnetic field absorption within a device results in increased photocurrent response in organic p-n junction diodes with gold nanoparticles. Compared with the same organic photovoltaic structures without gold nanoparticles, the proposed device shows about 40 % power efficiency improvement under halogen illumination. Experimental results agree well to the prediction of simulation, which showed SPR can be applied to enhance optical absorption of organic materials.

Date Published: 17 October 2007
PDF: 9 pages
Proc. SPIE 6656, Organic Photovoltaics VIII, 66561L (17 October 2007); doi: 10.1117/12.740676

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