Synthesis of zinc oxide and carbon nanotube composites by CVD method: photocatalytic studies

Abstract

The present work describes the synthesis of multiwall carbon nanotubes (CNT), zinc oxide (ZnO) and their photocatalytic evolutions. Nickel doped fumed SiO2 used as substrate for the synthesis of CNT by in chemical vapour deposition method. In-situ synthesis of ZnO:CNT composites was achieved in alkaline ethanolic medium with zinc chloride and CNT. The prepared composites were investigated by the Fourier Transform Infrared spectroscopy, confocal Raman spectroscopy, diffuse reflectance UV–visible spectrophotometer (DRS), X-ray diffraction, X-ray Photoelectron Spectroscopy (XPS), Brunaur–Emmett–Teller surface area and field emission scanning/transmission electron microscopy. The composites were employed in the degradation methylene blue and Reactive red-198 under visible light irradiation. The photocatalytic activity was determined by the spectrophotometric technique. The percentage of degradation was more for ZnO:CNT composites and shows higher capacitance, when compared to that of ZnO and CNTs. The recovered and reused catalysts catalytic activity was compared with that of fresh catalyst.