Enhanced luminescence of europium-doped layered double hydroxides intercalated by sensitiser anions

Abstract

Four sensitising anions naphthalene-1,5-disulfonate (15-NDS), naphthalene-2,6-dicarboxylate (26-NDC), benzoate (BA) and terephthalate (TA) were intercalated into a Eu(3+)-doped Zn/Al layered double hydroxide. The carboxylate anions enhanced the red luminescence of Eu(3+) much more strongly than the sulfonate, in the descending order TA > 26-NDC > BA > 15-NDS.

Layered Double Hydroxide Materials: Assembly and Photofunctionality

“…Figure 51c shows the polarized fluorescence measurements of the UTFs, and the degree of structural order can be obtained by detecting the fluorescence anisotropy r. The r value decreases from 0.15 at 20 C to 0.02 for UTFs at 100 C, which exhibit a less ordered arrangement of molecules at high temperature. [99] Similar observations can also be obtained for (CdTe QDs/LDH) 30 UTF [116]; Fig. 52a shows the responses toward temperature upon heating, and an intensity decrease along with red shift can be observed.…”

“…Additionally, the photosensitizer could also be incorporated into the interlayer of rare-earth-doped LDHs to obtain an advanced performance. For example, F€ orster resonance energy transfer (FRET) process could occur between the interlayer guest and doped ions in the host layer of LDHs [30][31][32], which leads to enhanced fluorescence. 4 LDH-Based UV-Shielding Materials and the Applications…”

Layer‐by‐Layer Assembly of Na9[EuW10O36]⋅32 H2O and Layered Double Hydroxides Leading to Ordered Ultra‐Thin Films: Cooperative Effect and Orientation Effect

“…For example, Lei et al. reported the enhanced luminescence of europium‐doped LDHs intercalated by sensitizer anions, in which both activator Eu 3+ ions and sensitizer organic anions were successfully incorporated into Zn 2 Al LDH 14a. Due to ready synthesis, facile chemical modification and biocompatibility, a family of LRHs15 have drawn wide attention.…”

Synthesis and characterization of hydrotalcite type structure containing Zn2+ and La3+-ions

“…Other than the popular coprecipitation technique, urea hydrolysis, acetamide hydrolysis, reaction of metal oxides in the presence of common anion, rehydration, and mechanochemical approaches have been employed to synthesize LDH [2][3][4]. Incorporation of lanthanide ions in a traditional LDH has been successful to a limited extent as their ionic radii (ranging from 0.85 to 1.04 Å) and preferred coordination numbers (ranging from 7 to 10) are higher than the prescribed limits to form the brucite layer structure having octahedral coordination [5][6][7][8][9][10][11][12][13]. Such a substitution has been reported to result in distortion of the lattice, micro-strain and crystalline morphology imperfections.…”