Enhancing conversion using diffusio-osmosis from patterned catalytic surfaces

Abstract

Alternating reactive and inert surface regions give rise to concentration gradients that drive fluid flow. The significance of this flow regarding transport phenomena has been studied numerically. An inhomogeneous catalyst surface leads to concentration gradients along this surface, which can generate diffusio-osmotic flows. The magnitude of this surface flow and the extent to which it impacts the catalytic conversion is numerically investigated and depends foremost on the reaction kinetics of the system and the surface-species interactions expressed via the diffusio-osmotic mobility. We present general scaling laws based on the reaction kinetics and interaction potential between chemical species and the catalytic surface, captured in a single parameter. We further investigate the optimal catalyst coverage in order to maximize the benefit of these surface flows.