LI Jiake, CHENG Kai, LIU Xin, WANG Yanxiang
(1. School of Material Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen, Jiangxi 333001; 2. Key Laboratory of Jiangxi Province for Advanced Ceramic Materials, Jingdezhen, Jiangxi 333001)
Abstract: ZnO superfine powder was synthesized by solution combustion method with sucrose and Zn (NO3)2·5H2O as raw materials.Effects of fuel/oxidant ratio (φ value) on phase composition, morphology, specific surface area, absorption spectrum and photocatalytic performance of synthesized powder were investigated by means of XRD, SEM, BET, Uv-vis,etc.. The results show that ZnO superfine powder (less than 150 nm in radial dimension) is synthesized with different φ value (0.5,1.0,1.5,2.0) at the ignition temperature of 500℃. Morphology, specific surface area and photocatalytic performance of synthesized ZnO vary with the change of φ. When φ =1.5, synthesized ZnO powder has the smallest average grain size (D=26.93nm), the largest lattice distortion (ε= -3.9×10-3) and the highest specific surface area (24.83m2·g-1). Therefore, the ZnO powder owns the highest photocatalytic activity, and the photodegradation rate of methyl orange (10mg/L) is 98.2% under the high-pressure mercury lamp irradiation for 60 min; besides, the photocatalytic reaction may be described with the pseudo first order kinetics equation.
Key words solution combustion method; fuel/oxidant ratio; ZnO superfine powder; morphology; photocatalytic performance