The direct transformation carbon dioxide emitted from the use of fossil fuels in energy, transportation and chemical process sectors involves its sequestration and then its storage or transformation towards a circular carbon economy, or its further valorization. In our laboratory we are interested in using renewable energy sources such as electricity from wind or solar cells or solar light reduce carbon dioxide to various C1 and C2 products. The research involves development of new inorganic compounds from a class of compounds called polyoxometalates that allow high fidelity synthesis and large potential of catalyst design.
The realization in the latter part of the 20th century that many syntheses practiced on a large scale were detrimental to the environment led to a movement towards reshaping the science of organic synthesis. The problems are particularly acute in the area of oxidation chemistry. Thus, the approach taken in this research is motivated or “pulled” by societal considerations that demand environmentally benign and sustainable solutions that demand environmentally benign and sustainable solutions for oxidative synthetic transformations in organic chemistry; broadly speaking this means the selective oxidation of hydrocarbons such as alkanes, alkenes and aromatics and other functionalized organic compounds, for example alcohols or sulfides.
Molecular oxygen is kinetically quite stable towards reaction at room temperature because of its triplet ground state and strong oxygen-oxygen bond. On the other hand the thermodynamic tendency for the reaction of O2 is combustion, that is to form carbon dioxide (CO2) and water (H2O). Thus, hydrocarbons typically react with O2 via a complex free-radical pathway termed autooxidation. These reactions are usually not selective and often have little synthetic utility. In order to overcome this limitation, in our group we are developing catalysts that catalyze reactions by new reaction pathways. Catalysis is used both to lower the activation energy of the reaction and to change the chemoselectivity of the reaction.