Cutting carbon nanotubes for solar cell application

This paper presents the application of cutting multiwalled carbon nanotubes ( cut- MWNTs ) in solar cell. Cutting of MWNTs is performed by plasma fluorination and followed by defluorination. Cut- MWNTs with lengths of 50 - 200 nm are incorporated in a poly ( 3- octylthiophene ) / n- Si heterojunction solar cell. We found that a device fabricated with cut- MWNTs shows much better performance than that of a device with pristine MWNTs. The device with cut- MWNTs shows short circuit current density, open circuit voltage, fill factor, and power conversion efficiency as 7.65 mA/ cm(2), 0.23 V, 31%, and 0.54%, respectively. Here, we proposed that cut- MWNTs provide efficient hole transportation having a few nanometer transportation path, hence suppressing recombination. Cut- MWNTs can be the solution to the shorting and shunting effects generally observed in the MWNT solar cell. (C) 2008 American Institute of Physics.