A conducting scaffold of carbon nanotube architecture has been used to anchor ZnO nanoparticles. The interaction between functionalized carbon nanotubes (f-CNT) and photoexcited ZnO nanoparticles results in direct electron transfer between the two systems. The role of f-CNT in facilitating the charge collection and charge transport in the f-CNT-ZnO composite film is elucidated by photoelectrochemical measurements.