Charge Carrier/Energy Transfer Within MOFs

Photon collection and sequential directional energy transfer are crucial steps in natural photosynthetic systems for the conversion of sunlight to chemical energy. The precise location and orientation of the organic linkers within porous, crystalline metal-organic frameworks (MOFs) allows us to study the fundamental aspects of charge transfer processes and subsequently employ them as photoelectrodes for solar energy conversion. Our group utilizes layer-by-layer or liquid-phase epitaxial growth to fabricate optically active MOF thin films in a well-controlled manner in order to study exciton transport within these films. For instance, we have used various spacers between optically active chromophores to tune the exciton transport distances within MOF thin films.  We are also exploring different chromophores to absorb various spectral ranges to systematically tune the Förster energy transfer efficiency.

Engendering electrical conductivity to porous MOFs promises to unlock the full potential of these materials for electrical energy storage, electrocatalysis, or integration of MOFs with conventional electronic materials. Inclusion of guest molecules within MOF cavities is an attractive strategy to impart electrical conductivity to these materials. Our group incorporates various guest molecules (e.g. C₆₀) in stable zirconium-based MOFs to tune donor (MOF linker)-acceptor (guest molecule) charge transfer interactions.