Using sunlight to catalyse demanding reactions

Research Project, 2020 – 2021

This project aims to utilize solar energy for CO2 transformation, using molecules for solar energy harvesting in combination with heterogeneous catalysis. The key challenge is the transfer of electrons from the light absorber to the catalytic reaction centre. New knowledge particularly focussing on reaction pathways and materials design, enabling utilization of sunlight for demanding catalytic reactions, will be generated.
 
The key is to break and make chemical bonds and here the catalyst provides electrons for this to be possible at lower activation energy. One dream reaction is to use the carbon atom in carbon dioxide as carbon source for synthesis of fuels and chemicals. However, the CO2 molecule is thermodynamically stable, and to reduce this molecule high amount of energy is required even in the presence of a catalyst. However, multielectron reactions lowers the activation barrier and yields more useful products. One way to provide this energy is to use sunlight in a photocatalytic fashion. Solar light capture using molecules is well researched and requires a molecule that absorbs light of the desired wavelength, and which can efficiently undergo excited state electron transfer to an acceptor. This could either be a molecular entity, or a material, e.g. a semiconductor, which can accommodate many electrons and serve as a charge reservoir.