Mesoporous ITO/NiO with a core/shell structure for supercapacitors

•Mesoporous ITO/NiO nanoarray electrode was successfully fabricated.•The electrode showed enhanced charge transfer and better electrolyte diffusion.•The electrode exhibits the specific capacitance of 1025 F g−1 at 1 A g−1.

In this study, a novel mesoporous NiO/ITO NW with a shell/core structure has been successfully synthesized by combining chemical vapor deposition (CVD) on titanium substrate and electrodeposition of HI–e (hexagonal lyotropic) nickel hydroxide through a lyotropic liquid crystalline (LLC) template, followed by calcination in air at 270 °C. The electrode material is characterized by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Both cyclic voltammetry (CV) and chronopotentiometry demonstrate enhanced electrochemical properties of NiO/ITO NWs composite electrode and improved supercapacitive behaviors as compared to bulk mesoporous nickel oxide film. Maximum specific capacitance of 1025 F g−1 at a discharge current density of 1 A g−1 in the potential ranges from 0 V to 0.5 V is determined by galvanostatic charge–discharge measurement in 1 M KOH solution. The newly synthesized heterostructure also possesses high capacitance retention ratio at high discharge current densities and long-term electrochemical stability in an alkaline solution. Therefore, this study provides a promising electrode engineering technique for various applications.

Graphical abstractMesoporous NiO/ITO nanowire with a shell/core structureFigure optionsDownload full-size imageDownload as PowerPoint slide