Construction of lanthanide multi-functional metal–organic frameworks via mixed ligand approach: Syntheses, structures, magnetic and luminescent properties

• Four Ln-MOFs were synthesized and structurally characterized.
• The maximum magnetic entropy change of 1 reaches ΔSmmax = 10.2 J kg− 1 K− 1 at 2 K.
• Compound 2 displays the typical luminescence of Dy3 + ions in the visible region.

Four isostructural lanthanide metal–organic frameworks (Ln-MOFs), [Ln2(BPDC)(BDC)2(H2O)2]n (Ln = Gd (1), Dy (2), Ho (3), Er (4)) have been synthesized via a mixed ligand approach based on 2,2′-bipyridine-3,3′-dicarboxylic acid (H2BPDC) and 1,4-benzenedicarboxylic acid (H2BDC) under hydrothermal conditions. TGA reveal the high thermal stability of these compounds. The magnetic properties of 1–4 have been studied. Weak antiferromagnetic interaction exists between Gd3 + ions in 1 and the maximum magnetic entropy change of 1 reaches 10.2 J kg− 1 K− 1 (22.9 mJ cm− 3 K− 1) for H = 7 T. Luminescent measurement shows the characteristic sharp emission bands of Dy3 + ions in 2.

Graphical AbstractFour lanthanide metal–organic frameworks [Ln2(BPDC)(BDC)2(H2O)2]n (Ln = Gd (1), Dy (2), Ho (3), Er (4)) were synthesized and characterized. 1 exhibits weak antiferromagnetic interaction and its maximum magnetic entropy change reaches 10.2 J kg− 1 K− 1 at 2 K. 2 shows the typical luminescence of Dy3 + ions.Figure optionsDownload as PowerPoint slide