| abstract |
We developed carbon nanotube-on-silicon heterojunction solar (photovoltaic) cells are provided with moderate efficiencies (>7%) and excellent air stability by integrating nanotechnology with silicon technology. The manufacturing process is simple and scalable, involving solution transfer of a uniform, single-layer or multilayer film of carbon nanotubes onto silicon surface to form heterojunctions (p-n) with high density, and does not require separation of metallic and semiconducting nanotubes. The nanotubes in the cells contribute to several processes that are critical for improving the efficiency, as a heterojunction component for charge separation, as a highly- conductive percolated network for charge transport, and as a transparent electrode for light illumination and charge collection. Control experiments indicate that the presence of semiconducting nanotubes is important in boosting the current densities and efficiencies. |