Preparation of N-Doped Double-Walled Carbon Nanotube-TiO₂ Hybrid With Efficient Visible-Light Photocatalytic Activity via a Two-Step Method.

Abstract

N-doped and double-walled carbon nanotube-modified TiO₂ (DWCNT-N/TiO₂) hybrid was synthesized using a two-step hydrothermal method and characterized using X-ray diffraction, UV-vis diffuse reflectance spectroscopy, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. DWCNT-N/TiO₂ photocatalytic activities were investigated on the basis of the photocatalytic degradation of sulfathiazole under visible light irradiation. Experimental results showed that DWCNTs in the hybrid were coated with N/TiO₂ nanoparticles, which facilitated close contact between the DWCNTs and N/TiO₂. Modification with DWCNTs contributed to the separation of photo-generated carriers and the absorption of visible light. N-doping provided the DWCNT-N/TiO₂ hybrid with enhanced absorption of visible light. The significant visible-light-driven photo-catalytic activity of the DWCNT-N/TiO₂ hybrid was caused by the synergetic effects of DWCNT modification and N-doping.