| In the 21th century, the research and development of material has evolved as the base for supporting the development of information. Metal oxide semiconductor materials have been the research focus due to their potential applications in magnetic, nonlinear optical, optoelectronic conversion, catalyst and sensing. In particularly, the research on the preparation of metal oxide material has attracted people’s great concern. This dissertation focused on the preparation of metal oxide materials on the basis of electrochemical corrosion principle, and meanwhile the effects of various parameters on the growth behavior of metal oxide materials were investigated as well.Firstly, the effects of sulfate ions on the growth behavior were investigated by using electrodeposition. The result showed that sulfate ion concentrations play an important role in controlling the phase evolution of prepared films. When ZnSO4 concentrations are below 0.54 mM, the oriented growth of ZnO rods is enhanced with the increase of ZnSO4 concentration. Otherwise, the vertically aligned zinc hydroxysulfate plates can be formed by the incorporation of SO2- ions in nanocrystals.Secondly, the effects of various parameters including chemical nature and concentration of electrolyte, Zn2+ concentration on the galvanic deposition of ZnO were explored by using the principle of macro-cell. The results showed that Zn2+ concentration exerts important effects on the morphology of ZnO. The taper-like ZnO crystals are apt to be produced at lower Zn(Ac)2 concentrations, while the rod-like ZnO crystals with enhanced orientation tend to be grown at higher Zn(Ac)2 concentrations. As to supporting electrolyte, ZnO nanorods are grow in KNO3 and KCl electrolytes, while sheet-like zinc hydroxysulfate plates are formed in K2SO4 electrolyte. Besides, KNO3 electrolyte is inclined to accelerate the passivation of Zn anode, resulting in the sharp decrease of driving force for galvanic deposition. In contrast, KCl and K2SO4 electrolytes facilitate zinc dissolution by anionic adsorption on the metal surface and subsequent participation in the active dissolution process, thus leading to the incorporation of anions into nanocrystals. Moreover, the increase of NaCl electrolyte concentration significantly increases the driving force of galvanic deposition, and meanwhile promotes the blue-shift of UV emission of ZnO. After air annealing at 300℃and 400℃, the UV emission is first enhanced then quenched sharply, while the visible emission tends to be enhanced tremendously. The origin of the changes in PL spectra after annealing is related to the introduction of new defect induced by the release of H and Cl dopants.Then, a facile route to prepare Cu2O crystals was described basing on the principle of galvanic cell, and meanwhile the effects of chemical nature on the growth behavior of Cu2O crystals were also elucidated. The results showed that the morphologies of galvanically obtained Cu2O crystals are mainly dependent on the nature of anions in aqueous solution. The cubic Cu2O crystals are formed in chloride media, while the truncated octahedral crystals are grown in sulfate. nitrate and fluoride media. Besides, the incoporation of Cl into Cu2O crystals occurs in cloride electrolyte.Finally, a simple route to synthesize ZnO decorated copper dentrites was detailedly demonstrated basing on the principle of micro-corrosion cell. The result showed that these’ copper dendrites possess a pronounced trunk and highly ordered branches distributed on both sides of the trunk. Meanwhile, both the trunk and branches are decorated with ZnO rods. The diffusion-limited aggregation (DLA) model was used to explain the fractal growth of Cu dendritic structures. This method provides a facile way to synthesize Cu/ZnO composites, which facilitates their potential applications in catalysts for methanol synthesis. |
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