A Supramolecular Artificial Light-Harvesting System with Excitation Energy and Electron Transfer

We present a supramolecular artificial light-harvesting system that combines excitation energy and electron transfer to drive chemical reactions. Different from the traditional artificial light-harvesting system, this tailored supramolecular assembly realizes the construction of a fully functionalized artificial light-harvesting system, including light capture, electron transfer, and solar-to-chemical energy conversion. A tetraphenylethylene derivative (D) was chosen as the antenna chromophores and coassembled with an iodide BODIPY (A) to produce a quadruple hydrogen-bonded supramolecular assembly. D was photoirradiated to an excited singlet state, subsequently undergoing excitation energy transfer (EET) to A with high efficiency (Phi(EET) = 95.3%). Then, excited A captured an electron from nearby D to generate radical ions D+center dot and A(-center dot), leading to charge-separation and chemical reactions. This supramolecular artificial light-harvesting system was used to produce an important chemical compound, hydrogen peroxide. In addition, it was applied to kill tumor cells by oxidizing NADH and generating cytotoxic reactive oxygen species.