Photoelectrochemical continuous flow N2 fixation into high value small organic molecules

• Applicants: Joshua Philip Barham, Ph.D.; Paolo Giusto, Ph.D., since 8/2023
• Subject Area: Physical Chemistry of Solids and Surfaces, Material Characterisation ; Organic Molecular Chemistry - Synthesis and Characterisation
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 501674274

The project aims to synthesize, characterize and utilize new heterogeneous photocathode materials in the reductive fixation of N2 into small organic molecules within organic solvents. The combination of redox energies from electrochemistry and visible light photons will equip the heterogeneous photocathode with sufficient energy to engage surface-bound N2 in reduction processes. Two types of heterogeneous photocathode materials will be investigated: i) alkali or first row transition metal carbon nitride incorporated photocathodes and ii) bilayered CuO/Cu2O composite photocathodes. The photoelectrochemical reduction of N2 will be paired with the electrochemical oxidation of small organic molecules, with the aim to upconvert these small organic molecules by N2 fixation into higher value amine, amino acid and azole compounds. Continuous flow reactors will be leveraged as ideal reactor platforms to handle gas-liquid photoelectrochemical reactions. Their ability to exert back pressure, reaching higher concentrations of dissolved N2, will favor the kinetics of N2 fixation reactions. Using organic solvent media instead of water further promotes the solubility of N2 and increases Faradaic efficiency by eliminating the competing electrochemical hydrogen evolution reaction of water. To aid SPP 2370 in the great challenge of N2 conversion, the project brings together an interdisciplinary team with expertise in heterogeneous material synthesis and characterization, organic synthesis, synthetic photoelectrochemistry and gas-liquid continuous flow chemistry.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2370: Interlinking catalysts, mechanisms and reactor concepts for the conversion of dinitrogen by electrocatalytic, photocatalytic and photoelectrocatalytic methods (“Nitroconversion”)
• Ehemaliger Antragsteller: Oleksandr Savatieiev, Ph.D., until 8/2023