(350j) Design of Nanoscale Hybrid Electrolytes Enabling Combined CO2 Capture and Conversion

Due to the rapid cost reduction of renewable energies, it is now possible to convert CO2 to chemicals and fuels using electrochemical pathways. In addition to catalyst development and reactor design, it is also important to consider the design of electrolytes that can effectively deliver CO2 to electrodes with desired product selectivity and reaction rates. Novel reactive materials have been shown to improve CO2 solubility, tune the selectivity of the CO2 reduction reaction and enhance reaction rates. In this study, Nanoparticle Organic Hybrid Materials (NOHMs)-based fluids have been designed as hybrid electrolyte systems that are capable of combined CO2 capture and conversion, without the need for a separate solvent regeneration step. Developing NOHMs-based electrolytes requires a fundamental investigation into the structuring and organization of these complex nanoscale fluids. A study of the mixing behaviors of NOHMs with a variety of secondary fluids has revealed that physical properties such as hydrodynamic size, viscosity and diffusion coefficient are highly dependent on the hydrogen bonding ability and size of the secondary fluid molecule. Additionally, it was discovered that the viscosity and the diffusion coefficient of the untethered polymer were found to scale according to theoretical predictions in the semi-dilute unentangled regime, while this was not observed for NOHMs-based fluids. Lastly, the CO2 solubility of NOHMs-based electrolytes has been measured and a change in the selectivity of the CO2 reduction reaction has been identified in the presence of these nanoscale electrolytes. The results of this work highlight the characterization and performance of a novel reactive medium designed for combined CO2 capture and conversion applications.