Multi-dimensional molybdenum-doped CuCoSe nanoflowers/CdSe nanodots/CuO nanowires for asymmetric supercapacitors

Three-dimensional (3D) Mo-doped CuCoSe (Mo-CuCoSe) nanoflowers and zero-dimensional (0D) CdSe nanodots are successively grown on the surface of one-dimensional (1D) CuO nanowires through a two-step electrodeposition strategy. As the supporting matrix, the 1D CuO nanowires can greatly alleviate the aggregation of the Mo-CuCoSe. The 3D Mo-CuCoSe nanoflowers show unique hydrangea-like structure, which can not only enhance the diffusion of electrolyte ions/electrons, but also facilitate the Faraday redox reactions. The 0D CdSe nanodots play a pivotal role in the enhancement of capacitance retentions. Due to the synergistic effect of CuO nanowires, Mo-CuCoSe nanoflowers and CdSe nanodots, the multi-dimensional CuO/Mo-CuCoSe/CdSe shows a high specific capacitance of 4600 mF cm −2 (at 1.0 mA cm −2 ) and excellent cyclic stability. Further, activated carbon (AC) and the multi-dimensional CuO/Mo-CuCoSe/CdSe are assembled to construct an asymmetric supercapacitor (ASC), which exhibits a maximum energy density of 30.3 Wh kg −1 at 214.2 W kg −1 .