A novel approach to large-scale formation of through-hole porous anodic aluminum template

A novel anodic oxidization equipment was designed to fabricate a large number of porous anodic alumina （PAA） templates in one time. This approach improved the efficiency of the preparation of the PAA templates remarkably in a normal lab and is expected to be used for the large-scale production in the future.

Synthesis and Characterization of Supported CulnSe2 Nanorod Arrays on Rigid Substrates

Copper indium diselenide nanorod arrays were electrodeposited on tungsten/silicon rigid substrates using porous anodic alumina as growth template. The porous anodic alumina templates were prepared by anodizing aluminum films which were sputtered onto the tungsten/silicon substrates. A selective chemical etching was used to penetrate the barrier layer at the bottom of the alumina channels before electrodeposition, which enables direct electrical and chemical contact with the underside substrate electrode. The as-deposited samples were annealed at 450 ℃ in vacuum. Scanning electron microscopy revealed that the nanorods were dense and compact with diameter of about 100 nm, length of approximate 1 um, and the aspect ratio of 10. X-ray diffraction, micro-Raman spectroscopy, and high resolution transmission electron microscopy showed that chalcopyrite polycrystalline structure and high purity CuInSe2 nanorods were obtained. The grain size was large in the rod axial direction. Energy-dispersive X-ray spectroscopy showed the composition was nearly stoichiometric. The energy band gap of this nanorod arrays was analyzed by fundamental absorption spectrum and was evaluated to be 0.96 eV.

Preparation and Optical Properties of V_2O_5 Nanotube Arrays

V2 O5 nanotube arrays in porous atomic alumina （ PAA ） template were obtained from V2O5 sols prepared by melt quenching method. X-ray powder diffraction and selected area electron diffraction investigations demonstrate that V2O5 nanotubes are orthorhombic. Results by scanning electron mieroscopy and transmission electron microscopy results shove that V2O5 nanotubes with a uniform diameter form highly ordered arrays. The diameter and length of the nanotubes depend on the pore diameter and the thickness of the PAA template used. It is proved that the sol-gel template process is a cost-saving , simple and readily-controlled method to prepare metal oxides nanomaterials .Owing to the quantum size effect. the optical absorption edge of V2O5 nanotubes in PAA ehibits a significant blue shift with respect to that of bulk V2O5.

Well-aligned carbon nanotube array membrane and its field emission properties

Ensembles of aligned and monodispersed carbon nanotubes (CNTs)can be prepared by templating method which involves fabrication of porous anodic aluminum oxide (AAO) template, control of catalytic iron particle size and chemical vapor deposition of carbon in the cylindrical pores of AAO. Here we show that template-synthesized CNTs can be fabricated as well-aligned nanoporous CNTs membrane, which can be directly used as an electron field emitter. A low threshold electric field of 2-4 V/μm and maximum emission current density of ～12 mA/cm2 are observed. The results also show that the electron emission current is a function of the applied electrical field and the Fowler-Nordheim (F-N) plot almost follows a linear relationship which indicates a Fowler-Nordheim tunneling mechanism, and the field enhancement factor estimated is about 1100-7500. The simple and convenient approach should be significant for the development of nanotube devices integrated into field emission displays (FEDs) technology.