Abstract
We obtained improved poly(3-octylthiophene) (P3OT)/C60 bulk heterojunction photovoltaic devices by doping with stable and highly electrically conductive Au and Ag nanoparticles. Doped devices showed 50–70% improved efficiency, with the Ag nanoparticles exhibiting the greatest increase in efficiency. We suggest that a dominate mechanism for the efficiency enhancement of doped photovoltaic device is the improved electrical conductivity through the introduction of “dopant” levels within the band gap of the P3OT.