| Nano-ZnO not only has surface effect, small size effect, quantum size effect and macroscopic quantum tunneling effect and other properties of nano-materials, but also has high transparency, high dispersion, making it show many special features in the optical, electrical magnetic, mechanical, catalytic, etc. It has a current wider prospect in the multi-functional inorganic materials. Therefore, the reasearch of nano-ZnO has become the focus of many scientists.It's an effective method to improve the electrical and optical properties by doping ZnO with particular element. In the optical performance, rare earth atoms have unfilled 4f5d electronic configuration, rich electronic transitions energy levels and long-lived excited state level. Very wide absorption and emission transitions can be generated in the UV - visible - IR spectral range; they can be used as the luminescence center of various light-emitting materials. Besides, rare earth metals are easy to disperse and can not be reduced, which has become the focus in the doped system. In the electrical performance, nano-ZnO is n-type conductivity, but its conductivity is not enough to be applied in practice. It's the most effective way to improve the nano-ZnO n-type conductivity by doping IIIA group element (Al, Ga, In). Because the radius of Al3+ is similar with that of Zn2+, which makes it more easily to be doped into ZnO and form solid solution. After aluminum being doped into zinc oxide, the conductivity can be greatly improved compared with that of pure zinc oxide, the transmittance of visible light has also been greatly improved. Al3+ doped ZnO (ZAO) is a kind of important transparent conductive oxide (TCO), and it is expected to replace the current expensive ITO, which has a very important research value.In this paper, ZnO nanomaterials were prepared with different morphologies by the complex-solvothermal method which is the combination of hydrothermal and solvothermal method. And on this basis Al or rare earth ion was doping into the ZnO nanomaterial, the morphology of the nano-ZnO, microstructure and electrical properties and optical properties were analyzed after doping these elements. The paper is summarized as follows:(1)ZnO nanorods were synthesized in the different surfactant assisted ethanol/water mixtures. By changing the experimental conditions, the proportion of reactants, additives, etc, a series of different aspect ratio and diameter of ZnO nanorods were prepared. The prepared ZnO nanorod aspect ratio was relatively large with PVP and CTAB as surfactant. With PVP or CTAB as the surfactant, ethanol as solvent, under temperature 120℃, via 24h reaction, the obtained ZnO nanorods had the maximum aspect ratio. They were smaller and did not contain any impurities, which was conducive to the research of the optical and electrical properties of the doped samples. UV-vis absorption and fluorescence spectroscopy showed that there were some defect states in ZnO nanorods.(2)Ce4+ ion was doped into the ZnO nanorods prepared with PVP as surfactant and ethanol/water as solvent, and then the morphology, structure and optical properties of the doped sample were characterized. The results showed that the size distribution of the ZnO nanorod with the introduction of Ce4+ broadened. The UV absorption spectrum of the ZnO nanorods doped with Ce4+ ion had a slight blue shift and broadened compared with that of the undoped ZnO nanorods. Fluorescence emission spectra of the samples showed the relative intensity of violet emission peak in ZnO nanorods doped with Ce4+ changed. When the doping concentration was lower, the diffraction peak of CeO2 didn't appear. The lattice constant increased, indicating that Ce4+ took the place of Zn2+, When the doping concentration was higher than 5mol%, the diffraction peak of CeO2 appeared in the XRD patterns, indicating that the excess Ce4+ ions would easily precipitate when the doping concentration of Ce4+ reached a certain value,.(3)Al3+ ion was doped into the ZnO nanorods prepared with PVP as surfactant and ethanol as solvent. It was found that the minimum resistivity of the sample was about 7.5Ω·cm in the electrical property test when the doping concentration was at 2mol%. UV absorption spectra of samples showed that the absorption peak position had a little blue shift, indicating that Al3+ ion was successfully incorporated into the ZnO lattice (4)Flower-like and sphere-like ZnO powder was synthesized with ethylene glycol/H2O as complex-solvent, and the structure, composition and optical properties of the two kinds of powders were tested. The prepared ZnO powder had uniform size distribution and didn't contain other impurity. It was found the product gradually changed from flower-like structure to sphere-like morphology by increasing ethylene glycol/H2O ratio,. Ammonium acetate and ethylene glycol played a key role during the formation of the structures. Ethylene glycol adsorbed on the surface of ZnO grain with the help of covalent or coulomb interaction and inhibited the growth of ZnO crystal. When NH4Ac was added, a new growth unit formed or the original growth unit was destroyed in the solution, which affected nucleation and growth process of ZnO.(5)Eu3+ was doped into the flower-like and sphere-like ZnO synthesized under ethylene glycol/water solvothermal conditions. In the lower doping concentration, the influence of doping Eu3+ on the morphology of flower-like ZnO was small. When the Eu3+ concentration further increased, the nano-particle size heterogeneity increased. The overall structure of flower-like structure was easily broken. XRD pattern showed that the lattice constant increased, indicating that Eu3+ replaced the site of Zn2+.Fluorescence spectra showed that fluorescence emission peak intensity was relatively high at lower doping concentrations.5D0→7F1 and 5D0→7F2 transition of the Eu3+ emission peak energy levels splited into two peaks, and the relative emission peak intensity was weak. It is believed that the splitting of emission peak was due to the crystal field symmetry and the location of Eu3+ within the grid. There was more significant impact on the sphere-like morphology and energy level splitting by doping Eu3+ into sphere-like ZnO.(6)Al3+ ion was doped into sphere-like ZnO structure. electrical performance test showed that when the doping concentration was 6mol%, the obtained Al3+ ion doped ZnO powders had a lower resistivity of about 4.5 x 103Ω·cm, the corresponding carrier concentration was in the 3x1014/cm3. When the doping concentration was higher (9mol %), there was a large impact on the sphere-like morphology by doping Al3+ into ZnO.(7)ZAO and the ATO conductive powder was synthesized with different doping ratio in 300℃,450℃and 600℃by molten salt method. The prepared ZAO powder mainly consisted with irregularly shaped particles, micron rod appeared partially. The minimum resistivity of ZAO powder prepared at 600℃was about 5 x 104Ω·cm, the highest carrier concentration was 2×1014/cm3. The prepared ATO powder mainly contained massive objects. XRD analyses showed that the diffraction peaks broaden, indicating that Sb3+ was doped into the lattice of SnO2. The lowest resistivity of the ATO powders prepared at 600℃was below 200Ω·cm, the carrier concentration was up to 5 x 1014/cm3.
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