Lanthanide-pamoate-frameworks: Visible light excitation for NIR luminescence

• A series of Ln-MOFs were synthesized by pH sensitive solvothermal method.
• TGA confirms these complexes are thermostable materials.
• Intense NIR emissions are obtained by exciting in the visible region.

Near-infrared (NIR) luminescent materials have been recognized of significance applications in bio-imaging, optical telecommunications, light emitting diodes and optical waveguides. Herein, a series of layer-structured Ln-MOFs which based on a conjugacy expanded ligand of pamoic acid were synthesized by pH sensitive solvothermal method. They are determined by single crystal X-ray diffraction, and further characterized by FT-IR, EA, TGA and PXRD. These complexes are isostructural and with the chemical formula of [Ln(PA)1.5(DMSO)3]n (Ln = Nd (1), Er (2), Eu (3), Gd (4) and Tb (5), H2PA = pamoic acid). They crystalize in trigonal space group R-3c and featuring 2D MOFs structures. TGA results confirm these complexes are thermostable materials. Interestingly, intense NIR emissions of Nd3+ and Er3+ complexes are obtained by exciting in the visible region, which suggesting the feasible applications of 1 and 2 in bio-systems.

Layer-structured Ln-MOFs were synthesized by pH sensitive solvothermal method. Intense NIR emissions of Nd3+ and Er3+ complexes are obtained by exciting in the visible region, which suggesting the feasible applications in bio-systems.Figure optionsDownload as PowerPoint slide