“…This is shown in Fig. 6 for the typical example of a 10 mC cm − 2 Ir oxide films in its predominantly oxidized state, (X o =0.8) and grown and studied in H 2 SO 4 [12,13,30,31], in that both electrons and ions are transported through them, yielding capacitive behavior at low frequencies, and transport controlled conditions Table 1 Characteristic impedance quantities for electron hopping and coupled electron-counter ion transport models [13,14] ): d, thickness of film (cm): F, Faraday constant (C/equiv): n e , number of electrons in reaction (equiv/mol): R, gas constant (J mol K): T, temperature (K): t e , t x , transport number of electrons and counter ion, respectively: z x , charge on counter ion (equiv/mol): i= 1+ (qm/RT):…”