The Capacitive Behaviors of Manganese Dioxide Thin-Film Electrochemical Capacitor Prototypes

Figure 2

SEM micrographs of MnO₂ thin film after cyclic voltammetric cycling in 0.2 M Na₂SO₄ liquid electrolyte for (a) 0 cycle, (b) 50 cycles (inset shows a spherical microparticle), (c) 100 cycles (inset shows enlarged microparticle with petal-like structure), and (d) 300 cycles.

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