(336h) Titanium Oxynitride Conformal Coating on Carbon Nanotubes As Energy Storage Materials

Compared with traditional secondary batteries, supercapacitors (SCs) take the advantages of high power densities, fast dynamics of charge properties and excellent cyclic performance. Recently, titanium oxynitride (TiON) has been developed as a novel and promising electrode material for SCs because it exhibits high thermal chemical stability and high electrical conductivity. In this presentation, amorphous TiO₂ thin film was firstly conformal coated on the surface of carbon nanotubes (CNTs) by controllable hydrolysis of titanium isopropoxide. Then the as-prepared TiO₂/CNTs was treated under ammonia gas to form titanium oxynitride-carbon nanotube composite (TiON/CNTs). The novel TiON/CNTs nanocomposite is systematically characterized by X-ray diffraction (XRD), high resolution transmission electron image (HRTEM) and X-ray Photoelectron Spectroscopy (XPS). The electrochemical supercapacitor with TiON/CNTs electrode is investigated by cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge-discharge. The specific capacity of this novel supercapacitor reached as high as 187 F g^-1 at a current density of 0.5 A g^-1, much higher than that of TiO₂/CNTs and CNTs. Its fair cycling performance demonstrated that it is a promising supercapacitor material for practical application.