Photoinduced charge transfer between poly(3-hexylthiophene) and germanium nanowires

Germanium nanowires (GeNWs) were used to enhance the properties of organic photovoltaic devices. GeNWs were grown to a length of 1–5μm on SiO2 by the vapor-liquid-solid method catalyzed by 20nm Au seeds. Once grown, the GeNWs were dispersed in solution with poly(3-hexylthiophene) and spin cast into films. The photoluminescence and external quantum efficiency of the films indicated a significant increase in exciton dissociation and photocurrent generation. The results imply that the GeNWs may act as an electron acceptor for bulk heterojunction hybrid-inorganic/organic photovoltaic devices. The impacts of GeNW on device characteristics are discussed.