3.5. RBS analysis
Fig. 5 shows the concentration of silver atoms per cm2 of thin films (4 41), (8 41), (8 4 2) and (8 4 4) (mean value of two
measurements). As shown in the Fig. 5, thin film (8 4 1) has a greater amount of silver atoms in relation to thin film (8 4 2). Conversely, thin film (8 4 4) was the one that exhibited the highest values for areal density of AgNPs. This difference occurred because,
for the system in which the pH of the PAA and PAH are distinct
(8.0 and 4.0), the AgNPs are repelled by PAA acid groups (last
deposited layer) upon immersion for 2 h, as discussed in
Section 3.3.1. The lowest silver concentration was observed in thin
film (4 41). These results are in agreement with the UV–vis
and GD-OES analyses.