Surface Patterning Increases Fluid Sorption Efficiency in Porous Reactive Coatings: A Model for Optimised Surface-Flow Filtration

Abstract A novel surface-flow filter has been designed to take advantage of a combination both diffusion and lateral flow permeation, since active coatings, even if porous, tend be far less permeable than through-flow constructs. The formation continuous coating layer virtually excludes any fluid transport into the other by planar for gases or capillarity liquids. This study considers additional potential creating pixelated/patterned coating, applied using pin coater form printed dots onto highly cellulose fibrous paper-like substrate. coating—fine particulate calcium carbonate combined with micro-nanofibrillated as binder humectant—reacts on exposure NO 2 gas nitrate. Experimental results show an effective doubling nitrate-forming efficiency pixelated compared reference coating. To establish understanding comparative mechanisms gas-coating contact, computational dynamic modelling is used generate surface pressure profiles pore network model estimate theoretical permeability coefficients. Although pressure-driven permeation was calculated approximately two orders magnitude diffusive flow, it concluded that patterned aerofoil differential effects can reduce impact stagnant layering so aid transfer, boosting transport, which in turn delivers greater contact based increased accessibility