Violet-blue photoluminescence in aluminium oxide films prepared by ultrasonic spray pyrolysis

Luminescence properties of oxide coatings on aluminum alloys

“…3 and Table 1): with λ exc = 275 nm the I 2 band in the photoluminescence spectrum is in its longest wavelength position with some contribution from the 390 nm (I 1 ) band, while with λ exc = 370 nm the I 2 band is some what shifted toward the blue with a minimal contribution from the I 1 band and has a minimal half width. With excitation in the These features of the photoluminescence and PLE spectra obtained by us for oxide films with an aluminum alloy substrate have been observed to some extent elsewhere [7,12,14,17] and are most similar to the results in [13,17]. For example, it is clear [13,17] that on going to long-wavelength detection the short-wavelength band near 275 nm is intensified in the PLE spectrum, much as we have detected in the 270-275 nm region.…”

“…A study of the interference of photoluminescence in anodic alumina films of different thicknesses formed at room temperature in oxalic and sulfuric acids showed [11] that the position and structure of the spectrum can depend on the film thickness. The nature of the photoluminescence in anodic alumina films and their applications are also discussed in [12][13][14][15][16][17][18][19][20]. …”

Efficient and tuneable photoluminescent boehmite hybrid nanoplates lacking metal activator centres for single-phase white LEDs

“…Luminescent metal oxide nanoparticles may offer a possible alternative to meet the material demand for ultraviolet-pumped WLED, mainly because of their high stability, simplicity, low toxicity and low cost. The fluorescence properties of Al 2 O 3 or g-AlOOH (boehmite) nanoparticles have already been studied [26][27][28][29][30][31][32][33][34][35][36][37][38] . For instance, these nanoparticles present emission in the ultraviolet and blue spectral regions due to lattice anion vacancies (F and F þ centres or grouping of these two defects) [30][31][32][33][34][35][36][37][38] excited through absorption of anionic vacancies below 300 nm, mismatching the pumped wavelength (350-420 nm) of commercial ultraviolet chips [26][27][28][29][30][31][32][33][34][35][36][37][38] .…”

Structural and Optical Characteristics of Gallium Oxide Thin Films Deposited by Ultrasonic Spray Pyrolysis

“…We have previously controlled these aspects in our pyrosol system to prepare uniform films of insulating and luminescent materials. [17][18][19] The starting solution was 0.05 M of gallium acetylacetonate ͑GAAc͒ dissolved in a mixture of 1 part deionized water and 1 part methyl alcohol. Glacial acetic acid was added ͑5 mL/L͒ to obtain a complete dissolution of the source material.…”