Photovoltaic property of a vertically aligned carbon nanotube hexagonal network assembled with CdS quantum dots.

A vertically aligned carbon nanotube (VACNT) hexagonal network was fabricated by plasma enhanced chemical vapor deposition as an electrode scaffold to assemble CdS quantum dots (QDs). The quantum dot sensitized solar cell (QDSSC) based on a VACNT/CdS hexagonal network shows a short circuit current density of 4.7 mA/cm(2), which is almost twice of that based on screen-printed CNT/CdS thin film with the same thickness. The enhancement of the short circuit current could be attributed to the unique morphology of the VACNT hexagonal network, which provides direct and percolating pathways for the electrons to transfer, enhances the spectral transmission through the hexagonal microchannels to the photoactive QD sites, and also presents more surface area to assembled CdS QDs without consuming extra substrate space. The photovoltaic property of the VACNT/CdS hexagonal network indicates its potential application in the energy conversion devices.