We report on the photoluminescence (PL) enhancement and morphological properties of highly ordered Nanoporous anodic alumina (NAA) fabricated by two-step anodization for 2–10 h at 5 °C and 25 °C anodization temperatures. Structural features and pore arrangements of NAA were characterized. Pore-properties such as pore-diameter, porosity and growth rate showed an increase with rising in temperature whereas pore-wall thickness and barrier layer thickness decreased, however, interpore distance and pore density were not affected. Two-dimensional fast Fourier Transform (FFT) analysis was used to study the pore arrangement. The average pore regularity ratio was higher at 5 °C. The Photoluminescence (PL) spectra of NAA samples exhibited a strong visible blue emission at room temperature. The broad PL peak was deconvoluted into two Gaussian sub-bands attributed to luminescent F+ and F centers. Experimental results showed that NAA prepared at elevated temperature showed PL enhancement by about 3.6–4.8 fold due to the increased anodizing current which leads to the increased density of F centers compared to F+ centers.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials