Fabrication of Alumina Nanowires From Porous Alumina Membranes by Etching in Phosphoric Acid Solution

Abstract

Alumina nanowires (ANWs) with high aspect ratios were synthesized by the chemical etching of porous alumina membranes (PAMs) in phosphoric acid solution. The morphology and structure of ANWs were analyzed by SEM and XRD, respectively. The results showed that the typical features of ANWs are around 35 nm in diameter and around 20 μm in length, the crystalline structure of the ANWs was amorphous, which was in accordance with that of the PAMs. Furthermore, the morphology of the PAMs was characterized by AFM and SEM in detail. On the basis of AFM and SEM observations, a possible formation mechanism of ANWs was discussed, and the inhomogeneous of the dissolution between the triple points and the side walls was considered to be the essential factor deciding the formation of ANWs.

In Situ Growth of Ultrasmall Nanochannels in Porous Anodized Aluminum Membrane and Applied in Detection of Lead Ion

“…Two-step anodization method was employed to fabricate a PAA membrane. − First, a scissors was applied to cut the aluminum foil into the desired shape and then ultrasonically washed with NaOH, ultrapure water, and absolute ethanol for 5 min. The first anodization was carried out in a phosphoric acid solution (0.4 M) as an electrolyte at 100 V for 120 min.…”

A Mercury Ion Electrochemical Sensor Based on Porous Anodized Alumina Membrane Nanochannels Modified with DNA

“…The preparation of PAA membrane.-A two-step anodization process was used to fabricate PAA membrane. [40][41][42][43] Single-sided anodizing device was shown in Figure 1. Prior to anodizing, the aluminum sheet with a radius of 45 mm was first ultrasonically cleaned in 1 M NaOH and ultrapure water for 5 min, then washed with absolute ethanol and dried with nitrogen.…”