Interfacial properties and interactions of two-dimensional flakes with substrates

This study examines how nanoscale adhesion, capillary forces, and degradation affect the behavior of metal pigments and 2D layers during flexographic printing. In tests transferring metallic pigment flakes onto polymer films to yield reflective coatings, additives segregated to the surface and boosted adhesion up to 10 wt-%. Evaluating core-shell pigments held in water for 48 days revealed that shell thickness decreased from 12–16 nm to about 6 nm. TEM–EDX and edge-resolved EDX showed that water penetration and core corrosion elevated oxide levels and depleted metal, impairing reflectivity. In addition, AFM testing of monolayer MoS2 on SiO2 showed that humidity enhanced tip adhesion through meniscus formation, with relative humidity over 39% causing water to slip beneath the sheet and increase its apparent height by around 0.32 nm.