Synthesis Of One-dimensional Titanium-based And Carbon-based Nanostructure Materials By Anodic Aluminum Oxide Template

Owing to the unique structure and excellent physical and chemical properties ofone-dimensional nanomaterials （fiber, wire, rod, belt and tube）, are widely used in manyimportant technological fields such as catalysis, sensors, batteries, electronic devicesand so on. The preparation technology of anodic aluminum oxide （AAO） is simple,moreover, the prepared porous AAO membranes have uniform pore distribution, poresize equal and adjustable. Thus, the AAO membranes as hard template are one of thegood choice for synthesis of one-dimensional nanomaterials. The main contents andresults are listed as follows:The various pore size AAO templates were prepared in the solution of sulfuric acid,oxalic acid and phosphoric acid with appropriate concentration via controlling theoxidation voltage. The pore distribution and pore structure of AAO template were alsosystemically characterized. In addition, some structure model of the AAO film and theformation mechanism of pore are also discussed. Experimental results show that porousAAO membrane with uniform pore diameter is perpendicular to the film surface andseparated parallel to each other, and can be easily controlled the pore size. We haveobtained20³0nm,40⁶0nm,160¹60nm pore size of AAO membrane in theelectrolyte of0.3mol/L sulfuric acid,0.3mol/L oxalic acid,10%phosphoric acid,respectively.The surfactant P123(EO₂₀PO₇₀EO₂₀) acting as the template agent, tetrabutyltitanate as titanium source and anhydrous ethanol as solvent, mesoporous TiO₂solprecursor was prepared in strong acid environment. The Al₂O₃decorated TiO₂nanotubes with ordered mesoporous pore walls （Al₂O₃/Meso-TiO₂nanotubes） weresynthesized by AAO template via vacuum pressure induction technology and in-situdeposition reaction, and the length and pore diameter of nanotubes depend on thethickness and pore size of AAO template. The morphology, composition and crystalstructure of samples were observed by using XRD, Raman, SEM, TEM and N2adsorption-desorption characterization means. The experimental results show that the samples have highly ordered mesoporous and tubular structure, larger specific surfacearea, in which Al₂O₃evenly distributed on the tube wall, and TiO₂with anatasestructure. The Al₂O₃/Meso-TiO₂nanotubes thin film electrode were fabricated bydropcasting solutions of Al₂O₃/Meso-TiO₂nanotubes, and to explore gas sensors oftesting NO_xwith high sensitivity and fast response time at room temperature.The Ni/hollow carbon nanofiber （Ni/HCF） composite was obtained by cylindernanopores of AAO template via heating decomposition of mixture precursor of glucoseand nickel acetate. Prepared samples have porous and hollow one-dimensionalnanostructures, nickel nanoparticles distributed evenly and highly dispersed on the wallof carbon nanofibers. The Ni/HCF composite has good adsorption properties, and gassensor response of functional nickel nanoparticles for nitrogen oxides （NO_x）. Theexperimental results show that thin film gas sensors of Ni/HCF composite detect NO_xgas to get fast response time and high sensitivity at room temperature.The sucrose as carbon source and Ni（Ac）₂as nickel source, magnetic porouscarbon nanofiber composite materials were prepared by AAO template, throughheat-treatment decomposition route. The obtained porous magnetic carbon nanofibercomposite was used as adsorption agent to investigate adsorption performance fororganic dye rhodamine B （Rh B） in aqueous solution. As for the adsorption anddesorption of Rh B,800oC carbonization sample has the largest adsorption capacity inall samples. In gas sensing test, the sensitivity of magnetic carbon nanofibers with adiameter of200nm film NO_xgas sensors are higher and relatively stable.