Facile Synthesis of Nanocrystal Tin Oxide Hollow Microspheres by Microwave-Assisted Spray Pyrolysis Method

Tin oxide (SnO2) hollow microspheres with narrow size distribution were prepared by a facile one-pot microwave-assisted spray pyrolysis method. The effect of temperature on microstructural and optical properties was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), high resolution transmission electron microscope (HRTEM), and UV-Vis spectrophotometer (UV-Vis), respectively. The SnO2 particles obtained at and above 700 degrees C are tetragonal rutile structure with high purity and smooth surface morphology, which consist of well-interconnected SnO2 nanocrystallines and the shell thickness was about 26 nm. UV-Vis absorption values were quite low in visible light region and high in ultraviolet region, indicating the possible utilization for optical purpose of the as-prepared SnO2. The band gaps were 3.88 and 4.07 eV for SnO2 synthesized at 700 and 800 degrees C, respectively. As compared to traditional electrical heating or flame modes, microwave heating introduced here demonstrates a high-efficiency, environmentally benign, and time- and energy-saving technology to synthesize advanced powders. (C) 2016 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.