Studies On The Growth, Structure And Properties Of One-dimensional Function Nanomaterials Synthesized From Hydrothermal Method

Using V2&5 and alkylamines (Cs-Cao alkyl chain) as precursor, vanadium oxide nanotubes which have an unique structure that alkylamines intercalate into layers of tubes wall affecting the layer spacing were prepared. Their layers spacing ranges from 1.25 nm to 3.82 nm according to the length of alkyl chain.Moreover, the growth mechanism of vanadium oxide nanotubes have been investigated and 3-2- ID model was established to interpret the vanadium oxide nanotubes growth process.Potassium niobate is a functional materials which can be used as photochemical catalysts.lt is well known that the catalytic activites are affected greatly by the surface area of catalyst particles on which the reaction take place. Nanoscale tubular structures possess larger specific surface and therefore lead to higher photo-catalytic activity. In this paper , two kind of niobate nanotubes with distinct structures were synthesized by hydrothermal reaction one of which have a special structure as potassium niobate does. The output of this nanotubes obtained by hrdrothermal method is very high . Nanotubes have anarrow size distribution which dismeter is about 30nm With several analysis methods such as HRTEM, EELS, XRD, SAED and so on the nanotubes' structure was characterized which can be regards as K^NbeOn structure. According to the SAED pattern, the axis of nanotubes can be determined which is along the crystal direction [100]. Moreover, the growth mechanism of this niobate nanotubes was investigated. The other nanotubes have a special structure which layer spacing is changeable according to the carbon chain length of alkylamines. The layer spacing changes from 2.2 nm to 3.3 nm .TiO2 is a functional materials with some outstanding physical and chemical properties which have many important application in areas including environmental purification, photocatalyst, and high effect solar cell. Research on TiO2 includes nanoparticals, thin film, mesoporous materials and titanium oxide nanotubes. In this paper, TiOx nanotubes were obtained by hydrothermal reaction from TiO2 and the mixture solution of NaOH and KOH. These nanotubes can be regards as H2Ti3O7 structure which have a narrow distribution in size which inter diameter and outer diameter are about 3 nm and 8nm, respectively. The growth process and optical properties of TiOx nanotubes were investigated.K2Ti6O13 is a wide band gap semicondcutor. Potassium titanate fibers have been shown to have high chemical and thermal stability and potential application in fiber-reinforced compounds. Many methods have been developed to synthesize the potassium titanate fibers including calcination, but typically the diameter of these fibers are always in micrometer scale. Previously, a simple hydrothermal method for preparing TiOx nanotubes by reacting TiO2 with the mixture solution of NaOH and KOH was described.More recent studies show nanowires products with narrow dismeter distribution around 5-10mn and lengths ranging from several hundred nanometers to several micrometers can be obtained if the mixture solution of NaOH and KOH was replaced by KOH solution. The nanowires were analyzed by a range of methods including powder X-ray diffraction (XRD), high resolution electron microscopy (HREM), selected area electron diffraction (SAED),electron energy loss spectroscopy (EELS), XRD and HREM image simulations. The structure of nanowires is determinded to be of the type of K2Ti6Oi3. Moreover, the growth mechanism of nanowires was investigated by the HRTEM observation. Finally, UV-VIS absorption experiments show that the potassium titanate nanowires are wide band semiconductor with a band width Eg~3.45 eV.