Titanium Sulfonate-Based Metal–Organic Frameworks

Abstract

Titanium-based metal−organic frameworks (Ti-MOFs) are one of the most active fields of MOFs due to their intriguing catalytic properties; however, the fast reaction between the widely used carboxylate-based ligand (hard base) and Ti 4+ ion (hard acid) makes the syntheses of Ti-MOFs extremely challenging. In this work, we propose a new strategy by adopting sulfonic acid (soft base) as organic ligands to synthesize Ti-MOFs based on hard and soft acid and base (HSAB) theory. As an example of this strategy, seven titanium sulfonate metal−organic frameworks have been synthesized from 1,5-naphthalenedisulfonic acid (H 2 nds) and titanium isopropoxide and their structures are determined by single-crystal X-ray diffraction. These compounds exhibit permanent porosity, solvent stability, and light adsorption ability with a narrow band gap (2.67 eV). This work demonstrates a powerful method for the single-crystal syntheses of new Ti-MOFs, which will greatly promote the development of Ti-MOFs.

Encapsulation of TixFeyLamOz nanoparticles into NH2-MIL-125(Ti) to fabricate a promising photocatalyst for the C–N coupling reaction

“…Metal–organic frameworks (MOFs), 21 due to their large internal surface area, 22 flexibility in designing the active sites, 23 chemical alteration, 24 pore structure, and high metal content, 25 provide valuable opportunities to design compounds with multiple applications. 26 MOFs are less thermally and chemically stable compared to porous mineral solids, even though some of them decompose when exposed to air or moisture.…”

A chelating coordination modulation method for the synthesis of Ti-MOF single crystals

“…8 Among MOFs, titanium-based metal–organic frameworks (Ti-MOFs) have garnered special attention due to their excellent photocatalytic activity. 9–21 Nevertheless, the scarcity of Ti-MOFs has limited the research in this area, with the focus mainly on two Ti-MOFs (MIL-125 and MIL-125-NH 2 ) reported over ten years ago. 22–24 Therefore, there is an urgent need to synthesize new Ti-MOFs.…”

Metal–Organic Frameworks with Triazine and Amine Functional Groups for Iodine Removal and Sensitive Detection of Cu2+ and Fe3+ Ions

“…As a new sort of functional porous materials, metal–organic frameworks (MOFs) or porous coordination polymers (PCPs) are well-known for their highly designable, large surface areas, and porous structures, which play an important role in numerous applications, such as gas storage, adsorption, separation, fluorescence sensing, etc. − A lot of MOFs have been applied in the removal or detection of pollutants. For example, [Al­(OH)­(tdc)], [Zr 6 ( μ 3 -O) 6 ­( μ 3 -OH) 2 ­(tdc) 4 ­(OH) 2 ­(HCOO) 2 ], and [Ce 6 ­( μ 3 -O) 4 ­( μ 3 -OH) 4 ­(tdc) 4 ­(OH) 4 ­(H 2 O) 4 ], based on the functional H 2 tdc (2,5-thio­phene­di­carb­oxylic acid) ligand, exhibited efficient removal of fluoride .…”