MnO2 modified TiN nanotube arrays on Ti mesh for flexible supercapacitors electrode

Abstract

A facile and economical strategy to develop a novel 3D binder-free and flexible electrode of supercapacitors with high performance was successfully designed by constructing MnO₂/TiN nanotube arrays (NTAs) on a Ti mesh substrate. Their phase compositions, microstructures and photo-electrochemical properties were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS) and electrochemical measurements. The results indicate that MnO₂ is filled in the bottom of the interval of 3D-TiN NTAs, and its thickness rises with the increase in the deposition cycles. Sample TM(200) exhibits a specific capacitance of 550 F g⁻¹ at a scan rate of 5 mV s⁻¹; its specific capacitance decreases with increasing scan rate. The specific capacitances in the TM series samples are far larger than those in TiN NTAs and T(200) samples. A mechanism is given to explain the excellent capacitive performance.