Six lanthanide(III) coordination polymers with 3,5-bis(4′-carboxy-phenyl)-1,2,4-triazole: syntheses, structures, and photoluminescence

Abstract

Six 3-D lanthanide(III)-metal-organic frameworks (MOFs) through multidentate 3,5-bis(4′-carboxy-phenyl)-1,2,4-triazole (H₂BCPT); acetic acid (HOAc); and corresponding trivalent rare earth chloride, {[Ln(BCPT)(OAc)(H₂O)]·(H₂O)}_n (Ln = Nd³⁺ (1); Sm³⁺ (2), Gd³⁺ (3), Tb³⁺ (4), Ho³⁺ (5), Yb³⁺ (6)), have been synthesized. MOFs 1–6 were characterized via FT-IR spectroscopy, elemental analysis, X-ray single-crystal diffraction, thermal analysis, and fluorescence. MOFs 1–6 are isomorphous, which can be described as a 3-D construction containing a dinuclear cluster [Tb₂(CO₂)₂(O)₂]. The 3-D structure with (4,4) topologies have been extended through BCPT²⁻ using μ₄-kO;kO;kO;kO coordination modes. Solid-state luminescence of 1–4 and 6 shows the characteristic bands of Nd³⁺, Sm³⁺, Tb³⁺, and Yb³⁺ from visible to near-infrared spectral regions.

Keywords:

• Lanthanide(III)-MOFs
• Structures
• Photoluminescence

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by the Science and Technology Research and Development Projects of Shaanxi Provincial [grant number 2013JM2015]; Natural Scientific Research Foundation of Shaanxi Provincial Education Office of China [grant number 2013JK0662]; the National Natural Science Foundation of China [grant number 21373178].