THE EFFECTS OF TiO2 BUFFER LAYER IN CARBON NANOTUBES GROWTH ON Ti SUBSTRATE BY THERMAL CHEMICAL VAPOR DEPOSITION AND THEIR ELECTROCHEMICAL PROPERTIES

Abstract

Carbon nanotubes (CNTs) have attracted considerable interest because of their unique physical, electrical properties and many potential applications. Carbon nanotubes are considered to be the most promising candidate in electrode materials for secondary battery, solar cell and supercapacitor. Non-conductive substrates, such as silicon wafers have usually been used to synthesize CNTs. However, in applications such as electrodes, it is desirable to have CNTs grown on conductive buffer layer and conductive substrates. We researched the fabrication of carbon nanotubes on Ni/TiO2/Ti substrate by Thermal chemical vapor deposition (TCVD). Experimental parameter is synthesis temperature, time and buffer layer thickness. The samples were characterized by means of field emission scanning electron microscopy (FE-SEM), Raman spectroscopy analysis, transmission electron microscope (TEM) and electrochemical test. The synthesized CNTs have the diameter of about 100~200 nm and the length of about 5~10 μm. Li/CNTs cell with CNTs on Ti substrate exhibited good charge/discharge behavior and slow capacity fading.