Aiko Kira

Supramolecular donor-acceptor heterojunctions by vectorial stepwise assembly of porphyrins and coordination-bonded fullerene arrays for photocurrent generation.

A novel strategy for constructing a vertical arrangement of bicontinuous donor-acceptor arrays on a semiconducting electrode has been developed. The relationship between the film structure and the photoelectrochemical properties has been elucidated as a function of the number of donor layers for the first time. The maximum incident photon-to-current efficiency value (21%) is comparable to the highest value (20%) reported for vertical arrangements of bicontinuous donor-acceptor arrays on electrodes.

Co-grafting of porphyrins and fullerenes on ZnO nanorods: Towards supramolecular donor-acceptor assembly

This work presents the synthesis and physico-chemical characterization of a novel artificial photosynthetic design, using anisotropic semiconducting nanorods as scaffolds to assemble organic donor-acceptor complexes on their surface. These hierarchical hybrid D-A assemblies were obtained by the co-grafting of porphyrins and fullerenes on the ZnO nanorods. Polarity of the solvent and porphyrin to fullerene ratios were investigated to be markedly influencing the donor-acceptor interaction under the co-grafted conditions on ZnO nanorods. Fourier transform infrared spectroscopy, cyclic voltammetry, electronic absorption and fluorescence spectroscopic techniques were used to characterize the formation and investigate the optoelectronic properties of porphyrin-fullerene complexes on the surface of ZnO. To the best of our knowledge, this is the first example of highly interacting porphyrin-fullerene complexes on ZnO nanorods, which may allow generating efficient nanosystems for artificial photosynthesis and harvesting of solar energy.