Improving photovoltaic response of poly(3-hexylthiophene)/ n - Si heterojunction by incorporating double walled carbon nanotubes

Poly(3-hexylthiophene)/ n - Si heterojunction solar cells were studied with and without incorporation of double walled carbon nanotubes (DWCNs) in the polymer layer. Performance of the device improves by manyfold by incorporation of DWCN. The authors report power conversion efficiency, open circuit voltage, short-circuit current density, and fill factor of 0.026%, 0.446 V , 0.3398 mA ∕ cm 2 , and 0.17, respectively, for an unoptimized cell containing DWCN. Reference cells without DWCNs show much lower performance. DWCN incorporation yields better hole transport, easy exciton splitting, and suppression of charge recombination, thereby improving photovoltaic action. DWCN seems promising materials for improving hole transport in organic solar cells.