Carbon dioxide (CO2) is a greenhouse gas that is a waste product of burning fossil fuels and is a byproduct of other industrial processes. Converting the carbon dioxide to fuels and chemical products reduces CO2 emissions and provides an alternative source of carbon for fuels and chemical feedstocks. One way this can be accomplished is using electricity and a "helper" molecule known as a catalyst to find an energy efficient reaction path in a chemical process called electrocatalysis. Two major challenges associated with electrocatalytic CO2 reduction are that the reactions are slow and that it is difficult to control the distribution of reaction products. In this project, Dr. Hailiang Wang is developing a new category of highly efficient catalysts for fast and selective electrochemical reduction of carbon dioxide to hydrocarbons. The catalytic sites of these materials are molecular in nature, so that synthetic chemistry can be utilized to accurately tailor the catalyst structures. The structures are further optimized at one the billionth of a meter level (the nanometer scale) to enhance their catalytic performance. The catalysts are insoluble in the electrolyte solution so that they can be easily separated. Dr. Wang is actively engaged in outreach activities that build upon his research to promote engagement of students in science, technology, engineering and mathematics (STEM) disciplines. These activities, which include a new outreach program named "Catalyzing a Sustainable Energy Future" based on the Energy Sciences Institute on Yale West Campus, are directed at improving the education of a diverse body of pre-college students and encouraging their interest in STEM careers.
With funding from the Chemical Catalysis Program of the Chemistry Division, Dr. Hailiang Wang of Yale University is designing metal-porphyrin molecular based heterogeneous electrocatalyst materials for efficient CO2 reduction to hydrocarbons. The approach combines the atomic-level structural tunability of molecules with the practical handling advantages of heterogeneous catalyst materials, to render new electrocatalyst materials with higher performance. The metal-porphyrin molecular structures are tailored by varying metal ions, introducing electronic substituents, incorporating proton donating groups, and designing selective intermediate stabilizing structures. The electrocatalytic performance are further enhanced by anchoring the metal-porphyrin molecules onto ancillary nanostructures. In-situ and operando X-ray absorption spectroscopic studies under electrochemical conditions and theoretical calculations and computational simulations are also performed to elucidate the reaction mechanisms. Dr. Wang is actively engaged in outreach activities that build upon his research to promote engagement of students in STEM disciplines. These activities, which include a new outreach program named "Catalyzing a Sustainable Energy Future" based on the Energy Sciences Institute on Yale West Campus, are directed at improving the education of a diverse body of pre-college students and encouraging their interest in STEM careers.
