Investigation of Structural and Luminescent Properties of Sol-Gel-Derived Cr‑Substituted Mg3Al1−xCrx Layered Double Hydroxides

Molecules

Arturas Katelnikovas¹  Ligita Valeikiene¹  Aleksej Zarkov¹  Aivaras Kareiva¹  Inga Grigoraviciute-Puroniene¹ 

[1] Institute of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius, Lithuania;

关键词: layered double hydroxides;    Mg₃Al₁;    substitution effects;    chromium;    photoluminescence;   

DOI  :  10.3390/molecules26071848

来源: DOAJ

【 摘 要 】

In the present work, Cr-substituted Mg₃Al_1−xCr_x layered double hydroxides (LDHs) were synthesised through the phase conversion of sol-gel-derived mixed-metal oxides in an aqueous medium. The chromium substitution level in the range of 1 to 25 mol% was investigated. It was demonstrated that all synthesised specimens were single-phase LDHs. The results of elemental analysis confirmed that the suggested synthetic sol-gel chemistry approach is suitable for the preparation of LDHs with a highly controllable chemical composition. The surface microstructure of sol-gel-derived Mg₃Al_1−xCr_x LDHs does not depend on the chromium substitution level. The formation of plate-like agglomerated particles, which consist of hexagonally shaped nanocrystallites varying in size from approximately 200 to 300 nm, was observed. Optical properties of the synthesised Mg₃Al_1−xCr_x LDHs were investigated by means of photoluminescence. All Cr-containing powders exhibited characteristic emission in the red region of the visible spectrum. The strongest emission was observed for the sample doped with 5 mol% Cr³⁺ ions. However, the emission intensity of samples doped with 1–10 mol% Cr³⁺ ions was relatively similar. A further increase in the Cr³⁺ ion concentration to 25 mol% resulted in severe concentration quenching.

【 授权许可】

Unknown