الفهرس 
Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
The present work is aimed to fabricate and characterize Low cost and efficient nanostructures based on porous anodic alumina membranes namely, carbon nanotubes/porous anodic alumina (CNTs/PAA), as well as ZnO decorated PAA membranes. Industrially pure aluminum foil in a 0.3M oxalic acid has been used effectively for forming such self-ordered PAA membranes. Tuning of the height and pore diameter for PAA with a highly uniform, ordered, nanoporous, arrayed structure has been successfully dealt with. The obtained results dealt with:
1. Hexagonally-aligned nanopores aligned vertically on Al substrate have been grown by two step anodization combined with pore widening process. The pore diameter is about 70 nm, the interpore distance is 100 nm, and the pore density is approximately 1.142 × 1010 cm-2. The EDX quantitative results of the membrane were 52% Al and 48% O for Al2O3.
2. For direct, simple, and cheap monitoring of heavy metals with concentrations varied from 1 to 100 ppb, CNT/PAA sensor has been developed. The metal detection involves rapid collection of dispersed metal-bound nanoparticles from a sample solution at the surface of the sensor, followed by the SERS measurements. The sensor was evaluated as a function of different concentrations and different elements.
3. 1D - ZnO nanorods have been successfully fabricated on the Al substrate when the starting precursor is Zinc acetate. The deposition of the Zn2+ nanorods inside the pores of PAAM has been carried out by the dip coating technique and followed by 30 min annealing in air at 600 oC. When the starting precursor is Zinc nitrate and the annealing has been carried out for 10 h at the same conditions, the ZnO nanoparticles are uniformly agglomerated into, almost, nanoseeds or nanocolloidal particles.
4. Ordered 2D ZnO nanotubes and nanorods were synthesized by oxidizing the Zn nanostructure arrays electrodeposited in the nanochannels of the PAA at 300 oC. The formation of Zn2+nanoarrays is attributed to the complete removing of the PAA barrier layer, the proper relativrates of deposition, and diffusion of Zn+2 ions according to Kirkendall effect. The fabricated ZnO (core) / ZnAl2O4 (shell) nanoarrays were used efficiently as a dye removal and a pH sensor.
from the previous results, it is concluded that CNTs/PAA nanoporous membrane is the suitable membrane for detecting very low concentrations of heavy metals and ZnO/ PAA membrane is an efficient nanoarray for the dye removal and pH sensor.