Carbon nanotube-modified electrodes for solar energy conversion

This review article deals with recent advancements on the application of carbon nanotubes, especially single-walled carbon nanotubes (SWNTs), to a photoactive layer on electrodes of photoelectrochemical devices and cells using liquid electrolytes. Versatile methodologies such as electrophoretic deposition, layer-by-layer deposition, self-assembled monolayer technique, and spray-coating have been adopted to form films of SWNTs on semiconducting or metallic electrodes. In the photoelectrochemical devices and cells, SWNTs can act as an efficient charge-transport pathway suppressing the back electron transfer or as a one-dimensional nano- and meso-scaffold for assembling photoactive molecules to facilitate the charge transport through the molecule arrays. These results demonstrate that the unique optical, electrical, and structural properties of SWNTs are beneficial for developing highly efficient carbon nanotube-based photoelectrochemical devices and cells.