Large area synthesis of well-dispersed β-MnO2 nanorods and their electrochemical supercapacitive performances

•Highly dispersed and homogeneous β-MnO2 nanorods are prepared in a large area.•A simple one-step hydrothermal synthesis in a controlled acidic condition is developed.•Excellent electrochemical capacitive performances are proved for these β-MnO2 nanorods.

Highly dispersed β-MnO2 nanorods are prepared by a simple one-step hydrothermal synthesis method. The structure and morphology of the β-MnO2 nanorods are investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The supercapacitive performances for the electrode made of β-MnO2 nanorods are investigated by cyclic voltammetry (CV) and galvanostatic charging-discharging (GCD). The SEM and TEM results show that these β-MnO2 nanorods have homogeneous 1-D nanostructures in diameter of about 55 nm and length of about 500 nm. When evaluated for supercapacitor electrode, a relatively high specific capacitance of 247.2 F/g is obtained at current density of 1 A/g in 1 mol/L KOH aqueous solution. And desirable rate performance and good cycling stability are also demonstrated for the well-dispersed β-MnO2 nanorods.

Graphical abstractHighly dispersed and homogeneous β-MnO2 nanorods are successfully fabricated in a large area, which displays excellent electrochemical supercapacitive performances.Figure optionsDownload full-size imageDownload as PowerPoint slide