Abstract: ZnO was prepared using zinc nitrate as source of zinc and sucrose as complexing agent by hydrothermal method.The effect of heat treatment on phase composition,microstructure and photocatalytic properties of synthetic products was investigated.Samples were characterized by XRD,SEM,ultraviolet-visible spectrophotometer and other testing methods.The photocatalytic properties of samples were evaluated by degradation of methylene blue solution.The results show that heat treatment is helpful to improve the crystalline structure and photocatalytic activity of ZnO.The degradation rate of sample after heat treatment to methylene blue reaches 98.4; when irradiated under high pressure mercury lamp for 240 min and 52.3 ; higher than untreated sample under the same conditions.

Key words: ZnO was prepared using zinc nitrate as source of zinc and sucrose as complexing agent by hydrothermal method.The effect of heat treatment on phase composition,microstructure and photocatalytic properties of synthetic products was investigated.Samples were characterized by XRD,SEM,ultraviolet-visible spectrophotometer and other testing methods.The photocatalytic properties of samples were evaluated by degradation of methylene blue solution.The results show that heat treatment is helpful to improve the crystalline structure and photocatalytic activity of ZnO.The degradation rate of sample after heat treatment to methylene blue reaches 98.4; when irradiated under high pressure mercury lamp for 240 min and 52.3 ; higher than untreated sample under the same conditions.