ZnO nanoparticles decorated multiwall carbon nanotube assisted ZnMgAl layered triple hydroxide hybrid photocatalyst for visible light-driven organic pollutants removal

Abstract

Multiwall carbon nanotubes (MWCNTs) supported by zinc-oxide nanoparticles with a ZnMgAl layered-triple-hydroxide (LTH) hybrid was synthesised via direct hydrothermal treatment. In the present investigation, the photocatalytic activity of the prepared hybrid materials was investigated using methylene blue and colourless phenol under visible light irradiation. The photocatalytic degradation efficiency of LTH, MWCNT, and MWCNT ZnO LTH is 48.11%, 4.4%, and 96.7% respectively. The prepared hybrid nanostructure shows a high photocatalytic property due to its synergetic effect, high charge carrier separation, and enhanced visible light absorption surface. The results indicated that the introduction of MWCNTs into the prepared catalyst can increase the photocatalytic activity because the oxidised MWCNTs act as a charge/electron transfer medium in the composite material. The trapping study was performed to examine the role of the active species in the photodegradation process. The abundance of more hydroxyl groups on the surface of the MWCNTs and in the LTH may efficiently improve the photocatalytic activity. The use of MWCNTs improved the catalytic activity of the prepared photocatalyst. The prepared hybrid material especially enhances the visible light absorption and, thus, the photocatalytic activity and cycle stability of the catalyst material.