Metal oxide nanostructures for electrochemical and photoelectrochemical water splitting

• Applicants: Professor Dr. Thomas Bein; Professorin Dr. Dina Fattakhova-Rohlfing; Professorin Dr. Rossitza Pentcheva; Professorin Dr. Christina Scheu
• Subject Area: Physical Chemistry of Solids and Surfaces, Material Characterisation ; Solid State and Surface Chemistry, Material Synthesis ; Theoretical Chemistry: Molecules, Materials, Surfaces
• Term: from 2012 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 220580381

The main goal of this research project is the development of novel metal oxide nanomorphologies for efficient electrochemical and light-driven water splitting. We will pursue a two-pronged search approach that is based on (i) computational screening using high throughput DFT calculations, and (ii) intensive collaborations within the SPP 1613 in the area of high throughput synthesis and testing. Optimized nano-morphologies at different levels of complexity will be developed, including thin film model systems, porous nanostructured films created through templating, and hierarchical structures. An important goal is to minimize losses due to limited carrier diffusion and recombination. Homogeneous doping, surface passivation and catalyst layers will serve to further enhance efficiency. Moreover, we will create electrode structures providing an additional driving force for rapid charge separation by means of stacked layers featuring materials compositions with different band edge positions. Complementary metal oxide nanomorphologies for the dark electrolysis of water will be developed with reduced overpotential, high available currents and improved stability. These synthesis efforts will strongly depend on the insights gained from the theoretical work and atomic scale characterization, where the impact of doping on the electronic structure will be investigated. Key insights from theory and electron microscopy will be fed back into the design loop described above, to further improve the efficiency of the photoelectrochemical and electrochemical cells. Degradation mechanisms will also be identified through analytical electron microscopy and strategies will be developed to increase the stability of the nanostructures.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1613: Regeneratively Produced Fuels by Light Driven Water Splitting: Investigation of Involved Elementary Processes and Perspectives of Technologic Implementation