A set of empirical equations describing the observed colours of metal–anodic aluminium oxide–Al nanostructures

• Cristina V. Manzano,
• Jakob J. Schwiedrzik,
• Gerhard Bürki,
• Laszlo Pethö,
• Johann Michler and
• Laetitia Philippe

Beilstein J. Nanotechnol. 2020, 11, 798–806, doi:10.3762/bjnano.11.64

• , as well as chemical or optical sensors. Experimental Fabrication of the AAO films Highly ordered anodic aluminium oxide (AAO) films were fabricated using a two-step anodization process [20][21][22] under the same conditions that were reported in previous manuscripts of our group [4][18]. The

• thickness and porosity of the nanostructures was determined, which describes a gamut of colours. The proposed mathematical model can be applied in different fields, such as wavelength absorbers, RGB (red, green, blue) display devices, as well as chemical or optical sensors. Keywords: anodic aluminium oxide

• (AAO) films; anodization; structural colours; reflectance; polar coordinates; plasmonic effects; Introduction Recently, the reproduction of the vivid colours found in nature has received increasing interest [1]. These colours appear when light interacts with periodic structures. With regard to this