New Approaches for Solar Fuel Production Using Metal-Organic Frameworks Based Heterogeneous Platforms

In a world that is running out of natural resources, there is a growing need to design and develop sustainable and green energy resources. Electrocatalytically driven reactions for the production of alternative fuels (water splitting or CO₂ reduction) hold the potential to provide a route for future carbon neutral energy economy. Nevertheless, the slow kinetics of those catalytic reactions demands the development of efficient catalysts in order to drive it at lower overpotentials. Indeed, a variety of molecular catalysts based on metal complexes are capable of electrochemically reducing CO₂ and/or protons.

In this talk, I will present our recent study on electrocatalytic CO₂ reduction activity of MOFs incorporating molecular catalysts such as Fe-tetraphenylporphyrin and Mn(bpy)(CO)₃Br.^[1] Our group utilizes Metal-Organic Frameworks (MOFs) as a platform for heterogenizing CO₂ reduction molecular catalysts. Their unique properties (porosity and flexible chemical functionality), enables us to use MOFs for integrating all the different functional elements needed for efficient catalysts: 1) immobilization of molecular catalysts, 2) electron transport elements,^[2] 3) mass transport channels, and 4) modulation of catalyst secondary environment.^[3] Thus, in essence, MOFs could possess all of the functional ingredients of a catalytic enzyme.

References:

[1] Hod, I.; Sampson, M. D.; Deria, P.; Kubiak, C. P.; Farha, O. K.; Hupp, J. T. “Fe-Porphyrin Based MOF Films as High-Surface-Concentration, Heterogeneous Catalysts for Electrochemical Reduction of CO₂”, ACS Catalysis, 2015, 5, 6302-6309.

[2] Hod, I.; Farha, O. K.; Hupp, J. T. “Modulating the Rate of Charge Transport in Metal–Organic Framework Thin Films Using Host:Guest Chemistry”, Chemical Communications, 2016, 52, 1705-1708.

[3] Hod, I.; Deria, P.; Bury, M.; Mondloch, J. E.; Kung, T. C; So, M.; Sampson, M. D.; Peters, A.; Kubiak, C. P.; Farha, O. K.; Hupp, J. T. “A Porous, Proton Relaying, Metal-Organic Framework Material that Accelerates Electrochemical Hydrogen Evolution”, Nature Communications, 2015, 6, 8304.