Accurate Assessment of the Oxygen Reduction Electrocatalytic Activity of Mn/Polypyrrole Nanocomposites Based on Rotating Disk Electrode Measurements, Complemented with Multitechnique Structural Characterizations

Figure 9

(a) RDE voltammograms (scan rate: 5 mV s⁻¹) of Mn-PPy240/G catalyst in O₂-saturated 0.1 M KOH at different rotation speeds. The N₂ background has been subtracted. (b) Koutecky–Levich plots derived from the curves of Panel (a) at a series of representative potentials. Symbols are experimental data; lines are the linear regressions. (c) Dependence of the electron transfer number on the electrode potential for three replicated samples. (d) Tafel plot obtained from RDE voltammograms at 1600 rpm.

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