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arXiv · 1209.4812

Effect of the anodization voltage on the porewidening rate of nanoporous anodic alumina

Mohammad Mahbubur Rahman·Enric Garcia-Caurel·Abel Santos·Lluis F. Marsal·Josep Pallares·Josep Ferre-Borrull
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Abstract

A detailed study of the pore-widening rate of nanoporous anodic alumina layers as a function of the anodization voltage was carried out. The study focuses on samples produced under the same electrolyte and concentration but different anodization voltages within the self-ordering regime. By means of ellipsometry-based optical characterization, it is shown that in the porewidening process, the porosity increases at a faster rate for lower anodization voltages. This opens the possibility of obtaining three-dimensional nanostructured nanoporous anodic alumina with controlled thickness and refractive index of each layer, and with a refractive index difference of up to 0.24 between layers, for samples produced with oxalic acid electrolytes.

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Mohammad Mahbubur Rahman, Enric Garcia-Caurel, Abel Santos, Lluis F. Marsal, Josep Pallares, Josep Ferre-Borrull. 2012-10-01. Effect of the anodization voltage on the porewidening rate of nanoporous anodic alumina. https://doi.org/10.1186/1556-276x-7-474

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