Study On Photocatalytic And Electrochemical Properties Based Tin Oxide Nanomaterials

In this thesis, several kinds of different morphologies of tin oxidemicro/nanostructures, such as hierarchical porous microflowers, core-shell microspheresand mesoporous nanospheres were prepared via a solution method under the mildcondition. Morphologies and microstructures of the as-synthesized products werecharacterized by Scanning Electron Microscope （SEM）, Transmission ElectronMicroscope （TEM）, X-ray diffraction （XRD） and Raman spectrometer. Effect of growthparameters on the morphologies of the as-obtained SnO2nanostructures wereinvestigated, the formation mechanisms of several unique SnO2micro/nanostructureswere proposed. The photocatalytic and electrochemical properties were also studied andthe photocatalytic mechanism of the as-synthesized SnO2nanostructures.Hierarchical porous SnO2microflowers were synthesized under an atmosphericcondition by using SnCl₂·2H₂O and H₂C₂O₄·2H₂O as the raw materials, and the mixtureof ethanol and polyethylene glycol as the solvents along with a following calcinationprocess. Morphologies and microstructures of the product were characterized throughSEM, TEM, XRD, and Raman spectroscopy. The results showed that the porous SnO2microflowers possess the rutile type tetragonal phase. A possible growth mechanismgoverning the formation of SnO2microflowers has also been discussed. Photocatalyticproperties of SnO2microflowers were investigated. The results showed that theobtained product exhibited a remarkable photocatalytic activity.Core-shell SnO2microspheres were synthesized by using SnCl₄·5H₂O and Sodiumhydroxide as the raw materials through a simple hydrothermal method at160oC withthe assistance of PVP. Microstructures of the product were characterized through SEM,TEM, XRD, and Raman spectroscopy. The morphology can be tailored by adjustingreaction temperature and the dose of Sn salt. Photocatalytic experimental results showedthat the core-shell SnO2microspheres exhibited excellent photocatalytic activities in theorganic dyes, which could be attributed to high specific surface area. Electrochemicalexperiments revealed that the microspheres also possess a very high reversible capacityand good cycling performance after20cycles.Mesoporous SnO2nanospheres were synthesized by using sodium stannate trihydrate as the raw materials through a simple hydrothermal method with the assistance ofglucose. The possible formation mechanism for mesoporous SnO2nanosphere wasdiscussed in detail, and it was found that glucose played a critical role for themorphology of the final products. Photocatalytic experiments of three differentmorphologies of SnO2were also conducted for the comparison.