Enhanced mass transport in electrochemical systems for renewable fuels and clean water
To meet the growing demand for green energy carriers and clean water for the next decades, we can use the increasing supply of harvested solar and wind energy to synthesize fuels (hydrogen, syngas, ammonia, etc.) and clean water via electrochemical methods. Electrochemical methods have the advantage of single-step, energy-efficient and low-temperature conversion of chemicals. However, despite developments in electrocatalysts and system design in the past decade, none of the electrochemical methods has grown to a market-leading technology in the energy or water sector because of limitations in process intensification. A boost in electrical current density, without sacrificing energy efficiency, is required to allow large-scale deployment.
This process intensification needs breaking three limitations in mass transport, at three different scales: 1) the diffusion boundary layer (microscale), 2) gas bubble interference (mm-scale) and 3) concentration gradients in the flow compartments bulk. This ERC project will use a multiscale approach to address these three mass transport limitations, and has the objective to understand and enhance mass transport using novel concepts. Diffusion limitations will be addressed via studying suspension electrodes, gas bubbles will be controlled while synergistically disturbing the diffusion boundary layer via pressure swing control, and reactor engineering concepts that are new to the field of electrochemistry are used to mitigate macro-scale concentration gradients. Water electrolysis, CO2 electrolysis and electrodialysis will be used as tool to evaluate these strategies, using fluorescence lifetime imaging (FLIM) and micro particle image velocimetry (μPIV) to observe the local environment at microscale within large-scale systems. This multiscale approach with in-situ measurements of local flow and concentrations will target the fundamental understanding and control of mass transport limitations for universal electrochemical conversion.