Study On Self-assembly Of ZnO/Ag Nanoparticles Heterogeneous Structures

Recently, Research on the application of semiconductor nanocrystals in micro-devices is attracting great deal of attention. Zinc oxide as common semiconductor material which is inexpensive, easily obtained was widely used in photocatalytic and photoelectric detectors. But the high band energy and low stability of zinc oxide limit the application of it greatly.Here in, ZnO/Ag micro-heterostructue was obtained through a solution method, which ZnO nanocrystles as nuclei and in contact with AgAc nanocrystals under the interactin of the acetate ion. A variety of characterization has been performed to give a possible mechanism of the self-assembly process of the heterostructure. results are as follows:(1) ZnO/Ag heterostructure with controllable morphology and components were synthesized. ZnO/AgAc structure was firstly self-assembled via solution method, AgAc then decomposed under 254 nm ultraviolet irradiation to form the ZnO/Ag heterostructure.(2) Characterized by SEM,TEM and FTIR,and in situ observation of the growth of the heterostructure with microscope, combined with series of control variables experiments, the bridge role of the acetate ion between ZnO and Ag+ was revealed and a possible mechanism of self-assembly based on diffusion-limited aggregation model was proposed.(3) Ultraviolet detector assembled with as-prepared Zn O/Ag microstructure was fabricated to demonstrate the application in photoelectric devices of the heterostructure.(4) To investigate the photocatalytic capacity of the ZnO/Ag heterostructure, organic pollutant(methylene blue(MB)) photocatalytic degradation experiments were comprehensive conducted. The result showed that as prepared ZnO/Ag heterostructure has a significant improvement in photocatalytic capacity than pure ZnO nanoparticles.