Inertially enhanced mass transport using 3D-printed porous flow-through electrodes with periodic lattice structures

Electrochemical reactors utilizing flow-through electrodes (FTEs) provide an attractive path toward the efficient utilization of electrical energy, but their commercial viability and ultimate adoption hinge on attaining high currents to drive productivity and cost competitiveness. Conventional FTEs composed of random, porous media provide limited opportunity for architectural control and engineering of microscale transport. Alternatively, the design freedom engendered by additively manufacturing FTEs yields additional opportunities to further drive performance via flow engineering. Through experiment and validated continuum computation we analyze the mass transfer in three-dimensional (3D)-printed porous FTEs with periodic lattice structures and show that, in contrast to conventional electrodes, the mesoscopic length scales in 3D-printed electrodes lead to an increase in the mass correlation exponent as inertial flow effects dominate. The inertially enhanced mass transport yields mass transfer coefficients that exceed previously reported 3D-printed FTEs by 10 to 100 times, bringing 3D-printed FTE performance on par with conventional materials.

Automated summary

Electrochemical reactors using flow-through electrodes offer a promising way to efficiently use electrical energy, but achieving high currents is crucial for their commercial viability and widespread adoption. Traditional FTEs made of random porous media have limited options for structural control, while additively manufactured FTEs provide more design flexibility to enhance performance through flow engineering.