Metal-organic framework supported metal-oxide semiconductor hetero-nanostructures for efficient photoelectrochemical water splitting (MOFMOX)

• Applicant: Professor Dr. Roland A. Fischer
• Subject Area: Solid State and Surface Chemistry, Material Synthesis ; Inorganic Molecular Chemistry - Synthesis and Characterisation ; Physical Chemistry of Solids and Surfaces, Material Characterisation ; Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 419949637

• Final Report Year: 2024

Final Report Abstract

Photoelectrochemical water splitting (PEC-WS) is a very attractive strategy to convert solar energy into chemical energy. Porous Metal–Organic Frameworks (MOFs) and MOF-based hybrid materials are promising photocatalysts owing to their inherent structural and physio-chemical properties. By suitable choices of organic linkers metal ion nodes and/or incorporation of photoactive metal-organic complexes the reactant adsorption, local enrichment and activation, the light absorption and the effective charge separation can be modified and leading to enhanced and even superior photocatalytic performance. However, there are still significant challenges for improving the MOFs’ intrinsic photocatalytic catalytic efficiency for practical application due to still limited visible light absorption, energy loss associated to fast recombination of photogenerated charge carriers and low materials stability. With MOFMOX, we intended to prepare photoanodes toward light-driven water splitting (oxygen evolution reaction) through the development of surface-grown MOF thin films (WP2) mainly acting as photosensitizers for interfacing with nanostructured metal oxides (WP1&2) mainly acting as catalytic materials and hosting of photoelectroactive additives and guests (WP3), for example, metal nanoparticles, followed by PEC testing and advance characterisations (WP4&5). While significant progresses have been achieved in WP2&3, interfacing MOFs with nanostructured metal oxides (WP1) remained challenging and turned out to be too time consuming to be accomplished as it was planned within the project. In particular, we could not efficiently set-up the intended collaboration with the partners at Palacky University Olomouc, which would have been essential for focusing on the assembly and the development of photoanodes. This has been partly due to the restrictions during the COVID-19 pandemic crisis 2020-2021. Thus, we decided to re-organise our project and focus our efforts on nanoscale MOF colloids that integrate molecular guests (catalysts as well as photosensitizers) for achieving semi-heterogeneous photocatalytic water-splitting thus satisfying the general catalytic goals of MOFMOX while keeping the strategic MOF-based design detailed in the WP3. The key milestone of this project has been the production of light-harvesting MOFs hosting two molecular catalysts to yield colloid, water-stable and versatile nanoreactors capable of photocatalytic syngas generation with controllable product ratios. Syngas, a mixture of CO and H2, is a high-priority intermediate for producing several commodity chemicals, e.g., ammonia, methanol, and synthetic hydrocarbon fuels. Accordingly, parallel sunlight-driven catalytic conversion of CO2 and protons to syngas is a key step toward a sustainable energy cycle.

Publications

• Entrapped Molecular Photocatalyst and Photosensitizer in Metal–Organic Framework Nanoreactors for Enhanced Solar CO2Reduction. ACS Catalysis, 11(2), 871-882.
  Stanley, Philip M.; Thomas, Christopher; Thyrhaug, Erling; Urstoeger, Alexander; Schuster, Michael; Hauer, Jürgen; Rieger, Bernhard; Warnan, Julien & Fischer, Roland A.
  
• Host–Guest Interactions in a Metal–Organic Framework Isoreticular Series for Molecular Photocatalytic CO2 Reduction. Angewandte Chemie International Edition, 60(33), 17854-17860.
  Stanley, Philip M.; Haimerl, Johanna; Thomas, Christopher; Urstoeger, Alexander; Schuster, Michael; Shustova, Natalia B.; Casini, Angela; Rieger, Bernhard; Warnan, Julien & Fischer, Roland A.
  
• Molecular Dye-Sensitized Photocatalysis with Metal-Organic Framework and Metal Oxide Colloids for Fuel Production. Energies, 14(14), 4260.
  Stanley, Philip M. & Warnan, Julien
  
• Porphyrinic MOF Film for Multifaceted Electrochemical Sensing. Angewandte Chemie International Edition, 60(37), 20551-20557.
  Zhou, Zhenyu; Mukherjee, Soumya; Hou, Shujin; Li, Weijin; Elsner, Martin & Fischer, Roland A.
  
• Porphyrinic MOF: Film Preparation and Properties of Electrochemical sensing/catalysis, Dissertation, TUM
  Z. Zhou
  
• Positioning of coordination-network materials at surfaces, Dissertation
  A. L. Semrau
  
• Surface-Mounted Metal–Organic Frameworks: Past, Present, and Future Perspectives. Langmuir, 37(23), 6847-6863.
  Semrau, Anna Lisa; Zhou, Zhenyu; Mukherjee, Soumya; Tu, Min; Li, Weijin & Fischer, Roland A.
  
• Understanding entrapped molecular photosystem and metal–organic framework synergy for improved solar fuel production. Faraday Discussions, 231, 281-297.
  Stanley, Philip M.; Parkulab, Mykhaylo; Rieger, Bernhard; Warnan, Julien & Fischer, Roland A.
  
• Vectorial Catalysis in Surface‐Anchored Nanometer‐Sized Metal–Organic Frameworks‐Based Microfluidic Devices. Angewandte Chemie International Edition, 61(8).
  Semrau, Anna Lisa; Stanley, Philip M.; Huber, Dominik; Schuster, Michael; Albada, Bauke; Zuilhof, Han; Cokoja, Mirza & Fischer, Roland A.
  
• Avoiding Pyrolysis and Calcination: Advances in the Benign Routes Leading to MOF‐Derived Electrocatalysts. ChemElectroChem, 9(7).
  Mukherjee, Soumya; Hou, Shujin; Watzele, Sebastian A.; Garlyyev, Batyr; Li, Weijin; Bandarenka, Aliaksandr S. & Fischer, Roland A.
  
• Decoupled Solar Energy Storage and Dark Photocatalysis in a 3D Metal–Organic Framework. Advanced Materials, 35(1).
  Stanley, Philip M.; Sixt, Florian & Warnan, Julien
  
• Merging molecular catalysts and metal–organic frameworks for photocatalytic fuel production. Nature Chemistry, 14(12), 1342-1356.
  Stanley, P. M.; Haimerl, J.; Shustova, N. B.; Fischer, R. A. & Warnan, J.
  
• Photocatalytic CO2‐to‐Syngas Evolution with Molecular Catalyst Metal‐Organic Framework Nanozymes. Advanced Materials, 35(6).
  Stanley, Philip M.; Su, Alice Y.; Ramm, Vanessa; Fink, Pascal; Kimna, Ceren; Lieleg, Oliver; Elsner, Martin; Lercher, Johannes A.; Rieger, Bernhard; Warnan, Julien & Fischer, Roland A.
  
• Topology- and wavelength-governed CO2 reduction photocatalysis in molecular catalyst-metal–organic framework assemblies. Chemical Science, 13(41), 12164-12174.
  Stanley, Philip M.; Hemmer, Karina; Hegelmann, Markus; Schulz, Annika; Park, Mihyun; Elsner, Martin; Cokoja, Mirza & Warnan, Julien
  
• Solar Fuel Production with Metal-Organic Framework and Molecular Catalyst Assemblies, Dissertation, TUM
  P. M. Stanley
  
• Analysis of metal–organic framework-based photosynthetic CO2 reduction. Nature Synthesis, 3(3), 307-318.
  Stanley, P. M.; Ramm, V.; Fischer, R. A. & Warnan, J.