Four series of lanthanide coordination polymers based on the tetrabromobenzene-1,4-dicarboxylate ligand: structural diversity and multifunctional properties

Suwadee Jiajaroen; Winya Dungkaew; Filip Kielar; Mongkol Sukwattanasinitt; Somboon Sahasithiwat; Hikaru Zenno; Shinya Hayami; Mohammad Azam; Saud I Al-Resayes; Kittipong Chainok

doi:10.1039/d2dt00007e

Four series of lanthanide coordination polymers based on the tetrabromobenzene-1,4-dicarboxylate ligand: structural diversity and multifunctional properties

Dalton Trans. 2022 May 17;51(19):7420-7435. doi: 10.1039/d2dt00007e.

Authors

Affiliations

¹ Thammasat University Research Unit in Multifunctional Crystalline Materials and Applications (TU-MCMA), Faculty of Science and Technology, Thammasat University, Pathum Thani 12121, Thailand. kc@tu.ac.th.
² Department of Chemistry, Faculty of Science and Technology, Thammasat University, Pathum Thani 12121, Thailand.
³ Department of Chemistry, Faculty of Science, Mahasarakham University, Maha Sarakham, 43100, Thailand.
⁴ Department of Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.
⁵ Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
⁶ National Metal and Materials Technology Center (MTEC), The National Science and Technology Development Agency, Pathum Thani 12121, Thailand.
⁷ Department of Chemistry, Graduate School of Science and Technology and Institute of Pulsed Power Science, Ku-mamoto University, 2-39-1 Kurokami, Chuoku, Kumamoto, 860-8555 Japan.
⁸ Department of Chemistry, College of Sciences, King Saud University, PO BOX 2455, Riyadh 11451, Kingdom of Saudi Arabia.

PMID: 35506589
DOI: 10.1039/d2dt00007e

Abstract

Four series of lanthanide-based coordination polymers (LnCPs), namely [Ln(Br₄bdc)_1.5(MeOH)₃] (1Ln; Ln = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy), [Ln₂(Br₄bdc)₂(NO₃)₂(MeOH)₄] (2Ln; Ln = Ce, Pr, Nd, Sm), [Ln(Br₄bdc)(NO₃)(MeOH)] (3Ln; Ln = Gd, Tb, Dy), and [Ln₂(Br₄bdc)₃(H₂O)_2.3(MeOH)_2.7] (4Ln; Ln = Gd, Tb, Dy) have been synthesized by reacting hydrated lanthanide(III) salts with tetrabromobenzene-1,4-dicarboxylic acid (H₂Br₄bdc) in different solvents under solvothermal conditions. The structural diversity found in the system mainly resulted from the effects of anions, solvents, and the variation in the ionic radii of the lanthanide(III) ions. Compounds in series 1Ln feature a two-dimensional (2D) layered structure with sql topology based on {(Ln(COO)₂)₂(μ-COO)₂} secondary building units (SBUs). Compounds in series 2Ln and 3Ln comprise, respectively, infinite uniform and alternate chains of {Ln(COO)₂}_n SBUs that are assembled into a similar network topology to 1Ln. Meanwhile, compounds in series 4Ln feature 3D coordination networks of a pcu α-Po topological net consisting of binuclear {Ln₂(COO)₃} SBUs. The formation of polymeric networks in series 1Ln-4Ln is facilitated by the numerous coordination sites of the ligand Br₄bdc^2- and the fact that its bromine atoms can participate in the formation of various types of intermolecular interactions. The solid-state photoluminescence studies on Eu- (1Eu) and Tb- (1Tb, 3Tb, 4Tb) containing compounds indicate that the Br₄bdc^2- ligands can efficiently sensitize Eu³⁺ and Tb³⁺ emission. Notably, such compounds exhibit highly sensitive fluorescence sensing for acetone, water, and Fe³⁺ ions via the fluorescence quenching effect. As the representatives of the series, activated 1Eu, 2Pr, 3Tb, and 4Tb show the maximum CO₂ uptake capacities of 170.4, 273.7, 255.3, and 303.5 cm³ g^-1, respectively, at 50 bar and 298 K with good repeatability of the adsorption-desorption properties. Magnetic studies indicate that the Gd- and Dy-based compounds 1Gd, 1Dy, 3Gd, 3Dy, and 4Gd show simple paramagnetic behaviours, whereas compound 4Dy exhibits weak ferromagnetic interactions.