Morphology Control And Properties Of Cuprous Oxide, Tungsten Oxide And Bismuth Oxychloride Micro/nano Materials

Due to their unique physico-chemical properties,nanomaterials are widely used in catalysis,sensing,energy storage and other fields.Therefore,preparation of novel semiconducting nanomaterials,controlling the size and dimension of the crystallites,and studying their growth mechanism have been investigated Hot spots.These studies will also promote people to study in depth the relationship between the micro-nano structure and the function of the material,efficient use of micro-nano structure and its industrialization.In this dissertation,novel Cu2O,WO3 · O.33H2O,BiOCl nanomaterials were prepared from the micro-nano materials of semiconducting metal oxides(Cu2O,WO3·0.33H2O,BiOCI)and their possible mechanisms were also investigated.Photocatalytic performance of semiconductor materials.The main contents of this thesis include the following aspects:(1)Hexagonal pyramid-like Cuprous oxide(Cu2O)nanoparticles have been synthesized by polyvinylpyrrolidone(PVP)-assisted hydrothermal method.The morphology of Cu2O samples with adding different amounts of PVP in solution was compared.Analysis results reveal that PVP plays a vital role in formation of hexagonal pyramid-like Cu2O nanoparticles in this work.According to the time-dependent experiments results,the probable formation mechanism of hexagonal pyramid-like Cu2O nanoparticles is discussed.Moreover,the products exhibit excellent photocatalytic activity for the photodegradation of phenol under visible light irradiation and the degradation rate approached to 83%.(2)Novel hierarchical hexagonal flower-like WO3·0.33H2O nanostructures(HHFWNs)have been successfully synthesized by hydrothermal method.We found that the hierarchical architectures of WO3·0.33H2O are self-assembled by a number of regular-shaped nanosheets of size 10～20 nm,which are cross-linked in the interior of the micro-hexagonal-flower.According to the time-dependent morphology evolution process,a possible formation mechanism is put forward.The effects of PEG-400 and H2O2 on the product are also studied.Furthermore,the photocatalytic activity of the obtained HHFWNs was investigated for the degradation of RhB under visible light illumination.The product exhibits excellent photocatalytic activity and has good stability and reproducibility.We believe that the present work will provide some ideas for further fabrication of other novel nanostructures and exploration of their applications.(3)flower-like BiOCl were prepared by solothermal method using Bi(NO3)3·5H2O and KCl as raw materials and ascorbic acid as reducing agent.Water and glacial acetic acid as a mixed solvent.The prepared BiOCl were characterized by SEM and XRD,showing that the as-synthesized product is pure BiOCl and consists of 3.0-4.0 μm flower-like structure.The optimum synthetic conditions are as follows:synthesis time 4h,sintering temperature 180℃,with which the prepared BiOCl has the best degradation rate toward rhodamine B reaches 98%in 20 min.