Fig. 6

(a) Nyquist plots of bare, 3DGH, NiO and 3DGH/NiO25 electrodes in 5.0 mM K₃Fe[CN]₆ containing 0.1 M KCl from 0.1 Hz to 100 kHz at an AC amplitude of 5 mV. (b) CVs response curves of studied electrodes in the absence and presence of 5 mM H₂O₂ in 0.1 M PBS (pH-7.4) at 50 mV/s.