A Series of Highly Connected Metal–Organic Frameworks Based on Triangular Ligands and d¹⁰ Metals: Syntheses, Structures, Photoluminescence, and Photocatalysis

Four novel highly connected metal–organic frameworks (MOFs) based on d 10 metals and triangular ligands, namely, [Ag 7 (4,4′-tmbpt)(HL) 2 (L)(H 2 O)] ( 1 ), [NaCd 3 (4,4′-tmbpt)(L) 2 (OH)]·H 2 O ( 2 ), [Cd 3 (3,3′-tmbpt) 2 (L) 2 (H 2 O) 2 ]·3.5H 2 O ( 3 ), and [Cd 3 (3,4′-tmbpt) 2 (L) 2 (H 2 O)]·1.5H 2 O ( 4 ) (H 3 L = 5-(4-carboxybenzyloxy)isophthalic acid, 4,4′-tmbpt = 1-((1H-1,2,4-triazol-1-yl)methyl)-3,5-bis(4-pyridyl)-1,2,4-triazole, 3,3′-tmbpt = 1-((1H-1,2,4-triazol-1-yl)methyl)-3,5-bis(3-pyridyl)-1,2,4-triazole, and 3,4′-tmbpt = 1-((1H-1,2,4-triazol-1-yl)methyl)-3-(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole) have been synthesized under hydrothermal conditions. Compound 1 features a three-dimensional (3D) (3,12)-connected net based on heptanuclear [Ag 7 (COO) 7 ] units. Compound 2 displays a 3D (3,4,10)-connected net constructed by tetranuclear [NaCd 3 (μ 3 -OH)(COO) 5 ] + units. Compound 3 exhibits a 3D (3,4,8)-connected net based on binuclear [Cd 2 (COO) 2 ] units. Compound 4 is a 3D binodal (3,9)-connected framework constructed by trinuclear [Cd 3 (COO) 4 ] units. The diverse structures of compounds 1 – 4 indicate that the central metals and the N-donor ligands have significant effects on the final structures. The photoluminescent properties of compounds 1 – 4 have been studied in detail. Remarkably, compounds 1, 2, and 4 exhibit photocatalytic activities for degradation of dye under UV light irradiation and show good stabilities toward UV-light photocatalysis.