Advances in the Synthesis of Covalent Triazine Frameworks

Abstract

Covalent triazine frameworks (CTFs) are a class of organic polymer materials constructed by aromatic 1,3,5-triazine rings with planar π-conjugation properties. CTFs are highly stable and porous with N atoms in the frameworks, possessing semiconductive properties; thus they are widely used in gas adsorption and separation as well as catalysis. The properties of CTFs strongly depend on the type of monomers and the synthesis process. Synthesis methods including ionothermal polymerization, amino-aldehyde synthesis, trifluoromethanesulfonic acid catalyzed synthesis, and aldehyde–amidine condensation have been intensively studied in recent years. In this review, we discuss the recent advances and future developments of CTFs synthesis.

Ruthenium nanoparticles on covalent triazine frameworks incorporating thiophene for the electrocatalytic hydrogen evolution reaction

“…38 Various studies concerning thiophene-containing CTFs are published, since the triazine moiety as an electron withdrawing group together with electron donating thiophene could constitute donor-acceptor (DA) polymers with low band gap and improved conductivity. [42][43][44][45][46][47][48][49][50][51][52][53][54][55][56] The primary route of CTF synthesis, the cyclotrimerization of oligo-nitrile precursors, is achieved via various ways, like ionothermal (ZnCl 2 ) or superacid-catalyzed polymerization, or amide condensation. Each way offers different advantages depending on the desired properties and intended applications.…”

Covalent Triazine Framework C6N6 as an Electrochemical Sensor for Hydrogen-Containing Industrial Pollutants. A DFT Study

“…In the recent past, several COFs have been utilized as sensors [ 44 ] for trinitrotoluene (TNT), picric acid [ 45 ], chromium (Cr), arsenic (As) [ 46 , 47 ] and iodine [ 48 ]. Previous reports show that covalent triazine frameworks (CTFs) are better sensors compared to COFs due to their controlled porosity, high density nitrogen cavities, high surface areas, high chemical and thermal stabilities, reproducible sensing responses and tuneable electronic properties [ 49 , 50 ]. These characteristics provide suitable conditions for the trapping and detection of analytes and infer the increased potential of CTFs as sensor surfaces compared to COFs.…”

A Steric-Repulsion-Driven Clutch Stack of Triaryltriazines: Correlated Molecular Rotations and a Thermoresponsive Gearshift in the Crystalline Solid

“…Triphenyltriazine, which contains three aromatic units connected to a central triazine ring with a C 3 -symmetric geometry, has been used as a functional building block for light-emitting organic materials. − Each aromatic unit can rotate around the axis of the C–C bond that connects it to the central triazine ring. In general, triaryltriazines form relatively tight π-stacked aggregate crystal structures given the multiple aryl rings present (Figure d). , This feature has been exploited to construct supramolecular polymer networks or covalent organic frameworks. , We envisioned that the introduction of bulky moieties at the peripheral aryl groups around the triazine core could create steric hindrance between neighboring triaryltriazine molecules and foster the formation of 60° offset stacked structures (henceforth denominated “clutch stacks”). Using this steric-repulsion-driven stacking event, the phenylene groups can be arranged above or below the center of the local space between the two phenylene rings of the neighboring triazine molecules (Figure e).…”

“…21,22 This feature has been exploited to construct supramolecular polymer networks or covalent organic frameworks. 21,22 We envisioned that the introduction of bulky moieties at the peripheral aryl groups around the triazine core could create steric hindrance between neighboring triaryltriazine molecules and foster the formation of 60°offset stacked structures (henceforth denominated "clutch stacks"). Using this steric-repulsion-driven stacking event, the phenylene groups can be arranged above or below the center of the local space between the two phenylene rings of the neighboring triazine molecules (Figure 1e).…”

“…In general, triaryltriazines form relatively tight π-stacked aggregate crystal structures given the multiple aryl rings present (Figure 1d). 21,22 This feature has been exploited to construct supramolecular polymer networks or covalent organic frameworks. 21,22 We envisioned that the introduction of bulky moieties at the peripheral aryl groups around the triazine core could create steric hindrance between neighboring triaryltriazine molecules and foster the formation of 60°offset stacked structures (henceforth denominated "clutch stacks").…”