Development of bioinspired artificial photosynthetic systems.

The specific objective of this review is to describe recent development of bioinspired artificial photosynthetic systems and their applications. First, multi-step electron-transfer systems composed of electron donor-acceptor ensembles are presented, mimicking functions of the photosynthetic reaction center. However, a significant amount of energy is lost during the multi-step electron-transfer processes. Then, as an alternative to conventional charge-separation functional molecular models based on multi-step long-range electron transfer within redox cascades, simple electron donor-acceptor dyads linked by covalent or non-covalent bonding have been developed to attain a long-lived and high-energy charge-separated state without significant loss of excitation energy. Such simple molecular dyads, capable of fast charge separation but extremely slow charge recombination, have significant advantages with regard to synthetic feasibility, providing a variety of applications including construction of organic solar cells and development of efficient photocatalytic systems for the solar energy conversion.