Photoinduced Charge Transport Through Inorganic Membranes

We are developing thin-film zeolites that generate long-lived, charge-separated states when illuminated by sunlight, allowing them to function as artificial photosynthetic membranes. As depicted in the figure below, ruthenium polypyridine photosensitizer molecules are tethered to one side of a zeolite membrane and bipyridinium electronacceptor molecules are encapsulated in the zeolite supercages. Photoexcitation of the ruthenium metal complex transfers an electron to a diquat ligand that is used to anchor it to the zeolite. The microporous nature of the inorganic zeolite enables the encapsulation of a wide variety of organic molecules, semiconductors, conducting polymers that can act as relays for charge migration. The electron on the diquat ligand can then be transferred from one side of the membrane to the other via hopping between supercages.