Rapid microwave-assisted fabrication of Al-doped zinc oxide nanorods on a glass substrate for photocatalytic degradation of phenol under visible light irradiation

Abstract

A rapid microwave-assisted process was used to synthesize a quasi-aligned Al-doped ZnO nanorods on a glass substrate. X-ray diffraction and scanning electron microscopy were used to investigate the crystal structure and morphological properties while the optical properties of the prepared materials have been examined by UV–visible and photoluminescence spectroscopy. Two different Al concentrations, 1% and 5%, were used to dope ZnO nanorods. The prepared Al-doped ZnO samples were annealed at 350 °C–550 °C temperature range. 1% AZO sample annealed at 550 °C showed the highest visible light absorption. Synthesized NRs surface chemistry have been characterized using X-ray photoelectron spectroscopy. Samples morphology, NRs density and diameter significantly changed with Al doping. Results show that the crystal orientation and surface oxidation states are dependent on Al content. Overall, Al-doping of ZnO NRs enhanced the photocatalytic degradation of phenol, especially at 1% Al due to bandgap narrowing and enhancement of visible light absorption.