Preparation of ITO Quai-1D Nanostructures by Sol-Gel Method Combined with Porous Anodic Aluminum Oxide Template
|School||Harbin Institute of Technology|
|Keywords||ITO 1D nanostructures sol-gel AAO template method hydrogen sensing proterties PL|
Tin-doped indium oxide （ITO） 1D nanostructures and ITO/C composite 1D nanostructures were fabricated by means of a sol-gel method utilizing porous anodic aluminum oxide template.The factors affecting the morphology of nanostructures were studied at the same time.Scanning electron microscopy（SEM）, Transmission electron microscopy, HRTEM,X-ray diffraction were applied to characterize the morphology and structure of the as-prepared nanostructures. The gas sensing properties towards H2 （1000 ppm）and pL properties of the the as-prepared nanostructures have been investigated.It has been demonstrated that the stable sol can be fabricated by sol-gel method through mixing In（NO3）3·4.5H2O and SnCl4·5H2O in acetylacetone or glycol ether.The sol can be as the precursor of ITO. The whole ITO nanostructures can’t be obastained by simplely dipping sol into the AAO template.The problem of less material depositing in nanohole of AAO template were solved by dipping sol into the AAO template many times.The 1D nanostructures can be obtained by increase dipping times.The straight, smooth ITO nanotubes were fabricated by means of dipping sol into the AAO template many times.The sol Concentration of ITO precursor was 1.5M and glycol ether was as solvent.The as-prepared ITO nanotubes exhibited a polycrystalline microstructure.The mean outer diameter of these nanotubes is about 250-300 nm, corresponding to the diameter of channels in the AAO template and the average thickness of the tube wall is about 25 nm. After postannealing at 550℃, X-ray diffraction pattern indicates that they are of a cubic bixbyite crystal structure and Sn4+ ions were homogeneously doped into the In2O3 crystal lattice.At the same time, ITO nanotubes and nanowires were fabricated by an improved sol-gol template method and Solvent Evaporation assistant method repectively.The as-synthesized ITO nanotubes showed excellent gas-sensing properties to H2 , which has a sensor response of 193s, a selectivity of 168%, recovering time of 20s at room temperature.Room temperature photoluminescence studies of the ITO nanotubes revealed a blue emission centered at 472nm. This was attributed to the singly ionized oxygen vacancy in the lattice of the ITO nanotubes.ITO/C composite 1D nanostructures were fabricated by means of a simple sol-gel method utilizing porous anodic aluminum oxide template. Room temperature photoluminescence studieds of the nanostructures revealed a ultraviolate emission. This work provides a new method of preparating composite 1D nanostructes.