Figure 6.

TEM micrograph of ZnO nanoparticles deposited in the ALICE. Depicted are representative micrographs obtained after nebulization of 1 mL of ZnO suspension (primary diameter 24-71 nm) with two different concentrations, a) 0.3 mg/mL and b) 7.5 mg/mL. As expected, the ZnO coverage increases with ZnO concentration and, although larger agglomerates are starting to appear for the higher concentration, their fractional contribution is still small. In both cases the deposition pattern is uniform not only on the mm scale as shown in Figure 5, but also on the scale of single droplets (micron scale). This is consistent with the formation of a continuous 14 μm liquid film after nebulization of 1 mL of suspension (estimated from deposition efficiency and chamber geometry), which implies that more than 4 droplets deposit on each location of the chamber.