Immobilized ZnTe magic-sized nanoclusters: a platform for powerful chemical reduction

• Applicant: Professor Dr. Michael Bredol
• Subject Area: Physical Chemistry of Solids and Surfaces, Material Characterisation ; Solid State and Surface Chemistry, Material Synthesis
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 504808434

The global problem with energy supply is caused by a decrease of the main energy sources such as gas, oil, coal or uranium and environmental degradation through, among others, huge emission of greenhouse gases, including carbon dioxide (CO2) into the atmosphere. This problem forces the search for new, alternative solutions. One of them is the use of solar radiation, which can be a source of energy but also can help, not only in the process of photosynthesis, to reduce the concentration of CO2 in the process of photocatalytic reduction.Solar-driven CO2 reduction would provide a perfect way for the conversion of technically abundant carbon dioxide (CO2) into practical chemical substances or fuels. Solar-driven CO2 reduction to CO or other valuable chemicals in solution is a extremely slow process due to unfavourable energetics of the intermediate CO2•- anion radical. ZnTe in principle could change this situation, because its conduction band edge is matching the energetic level of the CO2/CO2•- redox couple. The photochemical stability of ZnTe however will need dramatic improvements in order to make ZnTe a useful photocatalyst.This project therefore will design, synthesize and evaluate ZnTe in the form of “magic-sized nanocrystals”: nanoparticles with certain (small) numbers of ZnTe units are known to be much more stable than the average nanoparticle and therefore may open a way to prepare ZnTe photocatalysts and electrocatalysts with sufficient stability. The project will not only deal with preparation and characterization of such nanoparticles, but also look for methods to adsorb and stabilize them on conductive and non-conductive supports. Such nanocomposites then will be evaluated in terms of electrically biased and non-biased photocatalytic chemical reduction of CO2 (and potentially also other technically interesting entities like N2 or metal ions). Such an ambitious project can only be successful in an interdisciplinary approach: researchers from four different groups in Poland and Germany will be using their complementary expertise in the preparation of Zn-Chalcogenide nanoparticles, photoelectrochemical characterization of nanocomposites, analysis of surface chemistry and evaluation of electronic states at the band edge. The envisioned outcome of the project is a chemically simple and scalable (solar) (electro-) photocatalyst ready to make CO2 a useful resource for carbon-related chemistry.

• DFG Programme: Research Grants
• International Connection: Poland
• Cooperation Partner: Professorin Dr.-Ing. Katarzyna Matras-Postolek, Ph.D.