<title>Spectral investigation of porous anodic alumina film</title>

Abstract

Nanopore arrays were fabricated by self-organized anodization on aluminum. A two step anodization process was used to oxidize aluminum in H₂SO₄ solution. Hexagonally ordered pore array films were obtained by dissolving the remained aluminum base of anodic alumina in saturated HgCl₂ solution. Scanning electron microscopy and X-ray Diffraction were used to investigate the morphology and crystal structures of the porous anodic alumina films. An investigation was made on the optical transmission, optical absorption and photoluminescence of the porous anodic alumina films. The results show that the highly ordered anodic porous alumina films are amorphous. The transmission spectra and absorption spectra of porous anodic alumina films abruptly curve at wavelength of 360nm, the optical transmission increases at wavelength more than 360nm, the optical absorption increases at wavelength less than 360nm. The photoluminescence intensity and peak position of the porous anodic alumina films depend strongly on the excitation wavelength, there is a wide blue photoluminescence band in the wavelength range of 340- 600nm.