Two Ln-based metal–organic frameworks based on the 5-(1H-1,2,4-triazol-1-yl)-1,3-benzenedicarboxylic acid ligand: syntheses, structures, and photocatalytic properties

摘要

Two new metal–organic frameworks (MOFs) having the formula [Ln _(2) (H _(2) O) _(3) (L) _(3) ·3H _(2) O] _( n ) (Ln = Sm for MOF-Sm and Tb for MOF-Tb ) have been synthesized solvothermally by reacting LnCl _(3) ·6H _(2) O with 5-(1 H -1,2,4-triazol-1-yl)-1,3-benzenedicarboxylic acid (H _(2) L) and characterized. Single crystal X-ray analyses for MOF-Sm and MOF-Tb revealed that both MOFs are isostructural and display a (6,8)-connected 3D structure with a point symbol of (3 ~(5) ·4 ~(4) ·6 ~(6) )(3 ~(5) ·4 ~(6) ·5 ~(17) ). The natures of weak interactions existing in both MOFs have been assessed using Hirshfeld surface analyses and fingerprint plots. The utility of MOF-Sm as a photocatalyst for the safe photodegradation of the model aromatic dye methyl violet (MV) is also checked. The photocatalysis results showed that MOF-Sm offers reasonable photocatalytic degradation of this dye. The plausible photocatalytic mechanism of MOF-Sm aided photocatalysis has been explained with the help of band gap calculations using density of states (DOS) and partial DOS plots.