Ultrasonic Spray Pyrolysis Synthesis of Nanocrystalline InVO4 Hollow Microspheres and Their Visible-Light-Driven Photocatalytic Oxidation of NO
作者单位：Department of Civil and Structural Engineering Research Center for Environmental Technology and Management The Hong Kong Polytechnic University
会议名称：《第十届全国气溶胶会议暨第六届海峡两岸气溶胶技术研讨会》
会议日期：2009年
学科分类：07[理学] 070602[理学-大气物理学与大气环境] 0706[理学-大气科学]
关 键 词：InVO4 NO Visible light Photocatalysis Indoor air purification
摘 要：In this study, nanocrystalline InVO4 hollow microspheres have been synthesized by an ultrasonic spray pyrolysis synthetic method directly. The products were systematically characterized XRD, XPS, SEM, TEM, DRS, and nitrogen adsorption-desorption isotherms. The photocatalytic activity of the as-prepared hollow spheres was evaluated on the degradation of gaseous NO at 400 part-per-billion level under visible light and compared with a bulk InVO4 counterpart synthesized with a hydrothermal method. Results revealed that the as-prepared InVO4 hollow spheres exhibited higher photocatalytic activity than InVO4 bulk powders under visible light irradiation. This photocatalytic activity enhancement could be attributed to the special hollow structures, which were favorable for the diffusion of intermediates and the reduced deactivation of photocatalyst in the photocatalytic reaction. Fourier transform infrared spectroscopy （FTIR） results confirmed the formation of nitrate acid on the InVO4 surface during the photocatalysis of NO in the gas phase, revealing that the oxidation of NO molecules was the major process in this photocatalytic reaction. Multiple runs of the photocatalytic NO removal indicated that the InVO4 hollow spheres were stable. This study presents a promising approach for scaling-up industrial production of InVO4 hollow spheres with potential applications in photocatalytic indoor air purification.