Morphological and chemical characterization of highly ordered conical-pore anodic alumina prepared by multistep citric acid anodizing and chemical etching process

Initial Structural Changes of Porous Alumina Film via High-Resolution Microscopy Observations

“…Several unique properties, such as a high mechanical hardness, high corrosion resistance, and structural coloration can be achieved from the large-scale porous alumina film formed at high voltages. [25][26][27][28][29][30][31][32][33] Moreover, various ordered porous alumina films with a large cell structure measuring more than 500 nm in diameter can be fabricated. The most of anodizing process in etidronic acid reported previously operates under constant voltage conditions (potentiostatic anodizing) for the facile fabrication of ordered nanostructures.…”

Self-ordered anodic porous alumina with inter-hole spacing over 1.5 μm

“…There have been several reports on preparing highly ordered anodic porous alumina with large inter-hole spacing. [30][31][32] However, it was not easy to obtain the highly ordered anodic porous alumina with an interhole spacing over 800 nm under those anodizing conditions. The preparation of anodic porous alumina with inter-hole spacings of 1400-2036 nm has also been reported so for.…”

Electrochemical and morphological characterization of porous alumina formed by galvanostatic anodizing in etidronic acid

“…Advanced hard anodic coatings with microarc oxide/porous alumina double layers were successfully developed by inducing a steady plasma spark during etidronic acid anodizing at high voltages [31]. The fabrication of novel ordered nanomaterials, such as submicrometer-scale convex lens arrays [32], structural color devices [33], antireflective surfaces [34,35], and titanium dioxide nanocolumns [36], has been demonstrated through etidronic acid anodizing.…”