| One-dimensional nanomaterials have radius less than 100nm, length much larger than radial size and the aspect rario can reach tens even thousands. According to the structure and morphology of these materials, which are solid or hollow for example, one-dimensional nanomaterials can be divided into three different kinds, i.e. nanotubes, nanorods (or nanowires), nanobelts (or nanoribbons). Since their unique morphologies and excellent properties, one-dimensional nanomaterials have attracted great interests of researchers for decades.The research developments related to structure and hydrogen storage property of carbon nanotubes, and functional oxide one-dimensional nanomaterials, especially GeO2, B-Ga2O3 and ZnO were reviewed in this thesis. Until now, there aree still great disagreements in the hydrogen storage property of carbon nanotubes, and the reported experimental and theoretical results are too different to obtain a common conclusion. However, it is unfair for the time being to compare carbon nanotubes for hydrogen storage at the same level as metal hydrides or other established storage technologies, as not yet enough research has been carried out. On the other hand, functional oxide one-dimensional nanomaterials have become a new attractive research subject in the modern world, due to their excellent properties, specially, the novel electronic and optical properties.Using XRD and Raman spectrum, in the temperature range of 650-850℃, the rule of graphitization of multiwalled carbon nanotubes synthesized by catalytic decomposition of C2H2 was found: graphitization of multiwalled carbon nanotubes was improved with the increase of growth temperature. This phenomenon was closely related to the transportation and extraction rate of carbon atoms in the surface of catalysts at different temperatures. At lower growth temperature, the lower extracting rate of carbon atoms from catalyst particles due to the lower activity of the catalysts resulted in more defects formed in carbon nanotubes. Moreover, the lowertransportation rate of carbon atoms in catalyst particles also made lots of carbon atoms deposited on the surfaces of grown carbon nanotubes, or on carbon wrapped catalyst particles, even to form amorphous carbon layers. When the growth getting higher, the migration rate of carbon atoms was increased, more carbon atoms would pass through catalyst particles to contribute the growth of carbon nanotubes, which increased the growth rate and also resulted in less defects in carbon nanotubes. Another possible reason for this phenomenon is that with higher temperature, the mobility near defects of carbon atoms in grown carbon nanotubes would be also elevated, which gave carbon atoms higher mobility and have chance to readjus to decrease or eliminate some defects.A series of pretreatments and modifications including purification, annealing and doping were performed before hydrogen storage experiments carried out at room temperature under modest pressure (12MPa). The hydrogen source used is high purity of 99.9999%. For comparison, the annealing treatments were processed under ambient pressure in air and nitrogen atmosphere respectively. KNO3 solutions (0.1 mol/L and 1.0 mol/L) were used to dope carbon nanotubes. The results show that MWNTs annealed in nitrogen adsorbed more hydrogen than those annealed in air. FTIR spectra of the samples shows that the amount of oxygen functional groups linked to MWNTs after annealed in air was more than that treated in nitrogen. The former treatment may bring about more agglomeration of MWNTs, decrease the specific area and surface activity of MWNTs and eventually lead to lower capacity of hydrogen adsorption. The results also showed that with the same dopant, the capacity of hydrogen adsorption has great difference when the concentration of the doping solution changed. Hydrogen adsorption of MWNTs increased not only after doped in KNO3 solution but also with the increase of solution concentration in certain extent. After a typical adsorption/desorption cyc...
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