Table 1.
Comparison of electrochemical properties of Pt and Pt-Ir, determined using cyclic voltammetry at 20 mV/s (see Figure 1), in background electrolyte (PBS) and in PBS containing either 1 mM H2O2 or 1 mM AA. H2O2 and AA parameters were calculated following subtraction of the background current. Number of determinations, n = number of electrodes × number of scans.
| Parameter | Pt | Pt-Ir | p-value |
|---|---|---|---|
| Background scans | |||
| Current at the CV reversal potential (μA cm-2); n = 4 × 10 | 17.4 ± 1.1 | 16.6 ± 0.9 | 0.62 |
| Double-layer capacitance, Cdl (Eqn. 1; mF cm-2); n = 4 × 10 | 0.48 ± 0.02 | 0.45 ± 0.01 | 0.15 |
| H2O2 scans | |||
| Potential of maximum slope (Es,max, mV); n = 2 × 20 | 200 ± 5 | 195 ± 5 | 0.55 |
| Normalized maximum slope (Smax,N, mV-1) ; n = 2 × 20 | 0.45 ± 0.01 | 0.43 ± 0.01 | 0.30 |
| AA scans | |||
| Potential of maximum slope (Es,max, mV); n = 2 × 20 | 110 ± 5 | 115 ± 5 | 0.55 |
| Normalized maximum slope (Smax,N, mV-1) ; n = 2 × 20 | 0.59 ± 0.01 | 0.51 ± 0.07 | 0.38 |