Current generation of vertically aligned ZnO nanowires by photo-induced deformation of a matrix polymer

We report on the generation of current by applying strains onto vertically aligned ZnO nanowires (NWs) embedded in a coumarin-containing photosensitive P4VP-CMC polymer matrix. Upon irradiation of 365 nm UV light at 70 °C, polymer molecules are cross-linked to induce a strain on the embedded ZnO NWs while the cross-linked polymers are cleaved upon subsequent irradiation of 254 nm UV at 120 °C. We have systematically investigated the light induced reversible deformation of a polymer film, including the change of shape and the bond formation, which corresponded to the observed current generation.