Ruthenium Complex Containing Block Copolymer For the Enhancement of Carbon Nanotube Photoconductivity

We report the synthesis of a multifunctional block copolymer incorporated with pyrene and ruthenium terpyridyl thiocyanato complex moieties by reversible addition–fragmentation chain transfer polymerization. The pyrene block in the copolymer facilitates the dispersion of multiwalled carbon nanotubes in DMF solution because of the strong π–π interaction between the pyrene moieties and nanotube surface. On the other hand, the ruthenium complexes greatly enhance the photosensitivity of the functionalized nanotubes in the visible region. The photocurrent responses of the nanotubes at different wavelength measured by conductive AFM spectrum strongly agree with the absorption spectrum of the ruthenium complex. The results demonstrate a new and versatile approach in enhancing and fine-tuning the photosensitivity or other opto-electronic properties of carbon nanotubes by multifunctional block copolymers