Table 5 The electrochemical parameters extracted from impedance data of the scratched EC, NC2 and NC4 coatings immersed in 3.5 wt% NaCl solution.
Sample | Time/h | Rs (Ω cm2) | Rc (Ω cm2) | CPEc (F) | nf | Rct (Ω cm2) | CPEdl(F) | ndl |
|---|---|---|---|---|---|---|---|---|
EC | 24 | 2047 | 2.34 × 10–5 | 0.76 | 1.72 × 104 | 4.58 × 10–5 | 0.53 | |
72 | 1800 | 3.33 × 10–5 | 0.73 | 1.33 × 104 | 80.36 × 10–5 | 0.55 | ||
144 | 796 | 8.27 × 10–5 | 0.62 | 0.41 × 104 | 73.55 × 10–5 | 0.69 | ||
NC2 | 24 | 120 | 1204 | 1.39 × 10–5 | 0.79 | 3.52 × 104 | 7.21 × 10–5 | 0.50 |
72 | 95 | 4208 | 0.74 × 10–5 | 0.50 | 10.49 × 104 | 0.77 × 10–5 | 0.76 | |
144 | 50 | 5031 | 0.20 × 10–5 | 0.58 | 57.48 × 104 | 1.31 × 10–5 | 0.66 | |
NC4 | 24 | 50 | 1762 | 1.91 × 10–5 | 0.95 | 0.22 × 104 | 6.51 × 10–3 | 0.61 |
72 | 100 | 3181 | 8.75 × 10–5 | 0.56 | 23.05 × 104 | 9.53 × 10–5 | 0.99 | |
144 | 50 | 172 | 14.3 × 10–5 | 0.64 | 1.97 × 104 | 37.02 × 10–5 | 0.67 |
