Role of the oxidizing agent to complete the synthesis of strontium aluminate based phosphors by the combustion method. Issue 4 (10th December 2014)

• Record Type: Journal Article
• Authors: Rojas-Hernandez, R. E.; Rodriguez, M. A.; Fernandez, J. F.
• Is Part Of: RSC advances. Volume 5:Issue 4(2015)
• Page Start: 3104
• Page End: 3112
• Publication Date: 2014-12-10
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c4ra10460a
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Well-controlled fuel/oxidizing agent ratio allows to synthesize nanostructured strontium aluminates lamellar particles with high luminescence properties. Abstract : The influence of processing parameters on the phase formation of strontium aluminates doped with Eu 2+ and Dy 3+ by the combustion method has been evaluated. The addition of a slight excess of urea as a fuel has an important effect on the phase formation, but a larger amount of urea inhibited the strontium incorporation into the stuffed tridymite-like structure. The experimental results show that it is possible to incorporate a larger amount of urea than the theoretical one by adding nitric acid as an oxidizing agent. The presence of an oxidizing agent promotes both effective chelation of the cations and a higher crystalline order on strontium aluminate. Nanostructured lamellar particles have been obtained in a single step and the particles are well crystallized. The combustion method avoids the standard requirements of post-thermal treatments in a reducing atmosphere to promote the appearance of Eu 2+ cations. A higher amount of urea in the presence of the oxidizing agent produces strontium aluminate particles with higher phosphorescence brightness, owing to the increase of the reduction process Eu 3+ to Eu 2+ . The luminescence properties correlate with the crystallite size of the strontium aluminate. The results demonstrate a pathway to obtain phosphorescent pigments with sizes down to 10 μm.