Novel ZnO-Ag/MWCNT nanocomposite for the photocatalytic degradation of phenol

A novel Ag-doped ZnO nanoparticle with different amount of multi-walled carbon nano tubes (MWCNTs) was developed, aiming to shift the band edge toward longer wavelength. New particles were produced in a simple wet synthesis method and assessed toward the removal of phenol under UV-A illumination. The photocatalysts were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) with an energy-dispersive X-ray (EDX) spectroscopy analysis, transition electron microscopy (TEM), BET surface area analyzer, UV-vis diffuse reflectance spectroscopy (DRS) and photoluminescence spectroscopy (PL). The results indicated that all the samples containing MWCNTs exhibit higher photocatalytic activity than the bare ZnO and Ag doped ZnO nanoparticles. At a 10% MWCNT addition, the novel particle achieved a photocatalytic conversion rate of 81% in removing 100 ppm phenol under UV-A light irradiation after 240 min. The pH value, initial concentration and catalyst dosage were also found to influence the particle's photocatalytic performance significantly.