Fig. 1 shows XRD patterns of MnO2 and CuBi2O4-doped MnO2 thin films prepared by CBD on ITO glass and Ti foil. The results were shown respectively in Fig. 1a and b for CuBi2O4 doped-MnO2 with 0.00, 0.01, 0.03 and 0.05 g concentration on ITO glass and Ti foil. The intensive diffraction peaks appearing at 2θ=28.83°, 37.54°, 41.94°, 49.84°, 52.94° and 65.29° were indexed to the alpha-MnO2 [JCPDS card no. 44-141] and at 2θ=51.55° and 6178° were indexed to MnO2 [JCPDS card no. 12-713]. The peaks