Photocatalytic Activity of Carbon Nanotube/Zinc Oxide Nanocomposite for Solar Energy Based Water Treatment and Photoelectrochemical Water Splitting

Abstract

Fluorine doped Tin Oxide (FTO) was used as the substrate for the synthesis of Multi-Walled Carbon Nanotubes/Zinc Oxide nanorods composites. The first composite was a layer-by-layer sample of Multi-Walled Carbon Nanotubes/Zinc Oxide nanorods and the second was a mixed sample of Multi-Walled Carbon Nanotubes/Zinc Oxide nanorods. Characterisation techniques including XRD, FE-SEM and UV-Visible spectroscopy were performed on both the composites to investigate the diffraction peaks, morphology and band gap energy, respectively. Dye degradation and Photoeletrochemical (PEC) performance of both the composites were studied and the results proved that the photocatalytic activity and the photoelectrochemical performance were improved by the incorporation of MWCNT with ZnO nanorods. The highest dye degradation of 64.44% and 39.57% under UV and AM1.5G illumination and the highest photocurrent density of 1.5x10-4 A/cm2 and 8.0x10-5A/cm2 under UV and AM1.5G illumination were achieved by the MWCNT/ZnO layer-by-layer sample. This makes MWCNT/ZnO nanorods layer-by-layer sample a promising candidate for the removal of organic dyes from waste waters and for the production of Hydrogen as a source of sustainable energy by using the abundant light energy for water splitting.