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

Figure 8

RDE voltammograms (scan rate: 5 mV s⁻¹) in O₂-saturated 0.1 M KOH at different rotation speeds of (a) G, (b) PPy/G, and (c) Mn-PPy60/G electrodeposits. The N₂ background has been subtracted. (d–f) Koutecky–Levich plots derived from the curves of Panels (a, b, c) at a series of representative potentials. Symbols are experimental data; lines are the linear regressions. (g) Dependence of the electron transfer number on the electrode potential.

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