Figure 4
(a–d) 250–700 °C complex Z* plots of the air-, O2- and N2-processed BiT-Bi samples, and insets showing regionally enlarged drawings (the symbols: experimental data; the solid lines: fitting spectra). (e–h) 250–700 °C Z″/M″ plots of air-, O2- and N2-processed BiT-Bi samples. “CP” crystalline plate, “PB” plate boundary, “GB” grain boundary, “ED” electrode impedance, “W” Warburg impedance.
