Dr. Jennifer Strunk
|Photocatalysts for CO2 Reduction|
Development of active and selective heterogeneous photocatalysts for the reduction of CO2 to C1 building block chemicals
The aim of this project is the identification of a feasible way to reduce carbon emissions by chemical recycling of CO2 to important building block chemicals for industrial production. In particular, it focuses on the synthesis of methane and methanol, as these chemicals are needed in large quantities, not only for chemical production, but also as fuels for energy production. Instead of high-pressure processes with the consumption of hydrogen from fossile resources used today, the aim is the chemical conversion of CO2 only by the addition of water and the illumination with sun light in a photocatalytic reaction. However, active photocatalysts for the concomitant water splitting and activation of CO2 are hardly known yet. Within the scope of this project, active and selective photocatalyst systems based on semiconducting oxides are to be developed, and an optimization of the reaction parameters is desired.
|Selective alcohol oxidation in the liquid phase|
Another aspect of our investigations concerns heterogeneous catalysis in the liquid phase. Therefore we are interested in the selective oxidation of short chain alcohols, particularly ethanol and 2-propanol. To obtain insight into the reaction mechanism it is necessary to know about all products, by-products, and intermediates. This includes different species such as uncharged species and ionic species dissolved in the liquid and adsorbates on the catalyst surface. To get to know all of the present species and their conversion during reaction, different sophisticated characterization methods are used. It is possible to detect uncharged species with Membrane Inlet Mass Spectrometry (MIMS) while ionic species can be detected with Ion Chromatography (IC). IR-spectroscopy in attenuated total reflection (ATR-IR) is used to detect species that are adsorbed on the catalyst surface. Furthermore there will be isotopic exchange experiments (SSITKA, steady state isotopic transient kinetic analysis) to obtain deeper insight into the reaction mechanism and the conversion of the species into each other. The used set-up is shown schematically in Fig. 1.
Fig. 1: Schematic representation of the ATR-IR set-up including inlets for gas and liquid, MIMS and ion chromatography
Photocatalysts for CO2 reduction
In situ Infrared spectroscopy
(Sub)Monolayers of metal oxides on mesoporous silica
Influence of structural defects on catalytic activity