Photochemical Valorization of Carbon Dioxide

The reduction of CO2 emissions and ideally, the conversion of CO2 to high value products, are key elements of any effective climate intervention strategy. Thus, the photochemical fixation of CO2 to energy rich hydrocarbons for solar energy storage or feedstock chemicals for industry is both an attractive and daunting challenge that has attracted a great deal of interest. Many different approaches to CO2 reduction have been investigated, but the conversion of CO2 to desirable products as a result of vacuum UV irradiation is relatively unexplored. Our findings on VUV-induced CO2 reduction demonstrates that nearly 30% of CO2 can be converted under common photochemical reaction conditions when H2 and non-reducible oxides are present. Infrared spectroscopy provides evidence for a chain reaction mechanism initiated by VUV-induced CO2 splitting, which is enhanced in the presence of H2 and silica. Assuming improvements in lamp and reactor efficiencies with scale up, these results reveal a potential, simple strategy by which CO2 could be valorized.

Dr. Chao Liu is a postdoctoral researcher in the Gray research group. He obtained his B.S. in Chemistry from Guangxi University of China in 2008, and Ph.D. in Chemistry from the University of New Hampshire in 2015. His Ph.D. work focused on the development of heterogenized molecular catalysts and understanding the catalytic mechanisms in the utilization of carbon dioxide under electrochemical and photochemical conditions. In the Gray research group and in collaboration with Professors Justin Notestein and Eric Weitz, he has been working on the photochemical and thermal catalytic valorization of carbon dioxide.