High photocatalytic activities of zinc oxide nanotube arrays modified with tungsten trioxide nanoparticles

Publication date: January 2018 Source:Chinese Journal of Catalysis, Volume 39, Issue 1 Author(s): Yawen Li, Yuzhen Bu, Qian Liu, Xia Zhang, Junli Xu Well-aligned zinc oxide (ZnO) nanotube arrays loaded with tungsten trioxide (WO3) nanoparticles were synthesized by a process involving chemical bath deposition in combination with pyrolysis. The prepared ZnO–WO3 composites were characterized by X-ray diffraction, energy dispersive spectrometer, field emission scanning electron microscopy, X-ray photoelectron spectroscopy, photoluminescence spectroscopy, Fourier transform infrared spectroscopy and UV–vis diffuse reflectance spectroscopy. The photocatalytic activities of the ZnO–WO3 composite photocatalysts with different WO3 contents for the degradation of the herbicide chlorinated phenoxyacetic acid (MCPA-Na) under simulated sunlight irradiation were systematically evaluated. It was found that the WO3 content had a great effect on the photocatalytic activity of the ZnO–WO3 composites. The composite with 3% WO3 showed the highest photocatalytic activity, with a degradation rate of chlorinated phenoxyacetic acid of 98.5% after 200 min with 20 mg of photocatalyst. This photodegradation rate was about twice that of the pristine ZnO nanotube array. The recombination of photogenerated electrons and holes was increasingly suppressed with the addition of WO3 to ZnO. The high relative content of defects on the surface of the ZnO–WO3 composites was beneficial to their pho...
Source: Chinese Journal of Catalysis - Category: Chemistry Source Type: research