ound 97 ◦ for 4 and 5%w/w nanoparticle concentration.
Because the behavior reported in Fig. 3b for oil droplets is rather
surprising, experiments were repeated using dodecane which has a
surface tension(=25.3 mN/m) comparable to that of oil(=32 mN/m).
The results for dodecane droplets are presented in Fig. 3c: initially
s increases with nanoparticle concentration, it reaches a
maximum value (=134.2◦ at 2% w/w) and then decreases. Consequently,
the decrease of s at elevated nanoparticle concentration
is recorded for both oil (Fig. 3b) and dodecane (Fig. 3c) droplets. Itis
noted, that dodecane droplets were absorbed by coatings prepared
with nanoparticle concentration of 4 and 5% w/w and therefore s
measurements on these surfaces are not reported in Fig. 3c.