Researchers from University of Liverpool developed a laser-based spectroscopy technique that helps to analyze electrochemical reduction of CO2 in-situ
Abundant carbon dioxide (CO2) in the environment can be converted into energy-rich by-products such as methane and carbon monoxide (CO). However, the process consume more energy with less yield. Although electrocatalysts are an efficient option to achieve considerable amount of CO2 reduction, the operational mechanism of these catalysts is not understood, which acts as a hindrance in designing new electrocatalysts in a rational manner. Now, a team of researchers from Liverpool University’s Department of Chemistry in collaboration with Beijing Computational Science Research Center and STFC Rutherford Appleton Laboratory, developed a laser-based spectroscopy technique. The technique can be used to explore the electrochemical reduction of CO2 in-situ and offers required insights into these complex chemical pathways.
A technique called Vibrational Sum-Frequency Generation (VSFG) spectroscopy was used by the team along with electrochemical experiments to study the chemistry of a catalyst called Mn(bpy)(CO)3Br. The catalyst is one of the most preferred and intensely studied CO2 reduction electrocatalysts. VSFG enabled the team to observe major intermediates that are only present at an electrode surface for a short duration. The Cowan Group, a team of researchers who study and develop new catalytic systems for the sustainable production of fuels performed the work at Liverpool.
According to Dr. Gaia Neri, a member of the Liverpool team, distinguishing between the single layer of short-lived intermediate molecules at the electrode surface and the surrounding interference from inactive molecules in the solution is a challenge in studying electrocatalysts in situ. Neri further stated that VSFG enables to follow the behavior of very short-lived species in the catalytic cycle and thereby offers new opportunities to better understand the operational mechanism of electrocatalysts. The research is expected to facilitate commercialization of the process of electrochemical CO2 conversation into clean fuel technologies. The team is focused on enhancing the sensitivity of the technique and developing a new detection system for a better signal-to-noise ratio. The study was funded by the Engineering and Physical Sciences Research Council (EPSRC) and published in the journal Nature Catalysis on October 29, 2018.