One-step synthesis and morphology evolution of luminescent Eu2+ doped strontium aluminate nanostructures

Several shapes of Eu2+ doped strontium aluminate have been simply obtained by hydrolysis of Sr2+ and Al3+ in hydrothermal and solvothermal systems under mild conditions. The influence of reaction conditions on the formation of the samples has been considered. Flower-like nanoparticles are synthesized in glycol, when the solvent is substituted by H2O, and/or adding NaOH or stirring for 30 min before injecting the prepared Eu(NO3)3, needle cluster-like, sheet-like and lantern-like structures are synthesized. At the same time, the doped Eu3+ is reduced to Eu2+ at much lower temperature, and the emission peaks result from the transition of 4f65d–4f7 of Eu2+ around 405 nm, 435 nm and 530 nm are also observed, no typical peak of Eu3+ is found, which indicates the complete reduction from Eu3+ to Eu2+. The results of this article may give a guide to synthesize the similar Eu2+ doped luminescent materials.