Capture and conversion of CO2 to methanol using a renewable source of H2 is a promising way to reduce net CO2 emissions while producing valuable fuels. Design of an efficient heterogeneous catalyst for CO2 hydrogenation is critical for the large-scale implementation of the CO2 to methanol process. Combining both capture and conversion of CO2 in a single material has the potential to reduce the overall cost through process intensification. We have used density functional theory to computationally design a catalyst capable of producing methanol from CO2 and H2, including calculating the reaction pathways and barriers of each step. The catalyst consists of a microporous metal organic framework (UiO-67) functionalized with catalytically active Lewis pair functional groups. Our calculations indicate that this novel catalyst facilitates the heterolytic dissociation of H2 to generate hydridic and protic H atoms bound to Lewis acid and base sites, respectively, which facilitates a series of simultaneous transfer of two hydrogens to produce methanol: (Chemical Equation Presented). Importantly, our catalyst binds H2 more strongly than CO2, which prevents CO2 from poisoning the Lewis acid and base sites.
Bibliographical noteFunding Information:
We gratefully acknowledge the support from U.S. Department of Energy (Grant No. DE-FG02-10ER16165). The computations were performed at the University of Pittsburgh's Center for Simulation & Modeling and at the Extreme Science and Engineering Discovery Environment (XSEDE) under project TGDMR110091.
© The Royal Society of Chemistry 2016.