Covalent triazine framework with efficient photocatalytic activity in aqueous and solid media

Abstract

Covalent triazine frameworks (CTFs) have been recently employed for visible light-driven photocatalysis due to their unique optical and electronic properties. However, the usually highly hydrophobic nature of CTFs, which originates from their overall aromatic backbone, leads to limitations of CTFs for applications in aqueous media. In this study, we aim to extend the range of the application media of CTFs and design hybrid material of a CTF and mesoporous silica (SBA-15) for efficient photocatalysis in aqueous medium. A thiophene-containing CTF was directly synthesized in mesopores of SBA-15. Due to the high surface area and the added hydrophilic properties by silica, the hybrid material demonstrated excellent adsorption of organic molecules in water. This leads not only to high photocatalytic performance of the hybrid material for the degradation of organic dyes in water, but also for efficient photocatalysis in solvent-free and solid state. Furthermore, the reusability, stability and easy recovery of the hybrid material offers promising metal-free heterogeneous photocatalyst for broader applications in different reaction media.

Organic Covalent Interaction‐based Frameworks as Emerging Catalysts for Environment and Energy Applications: Current Scenario and Opportunities

“…[147] CTF-Th@SBA-15 is recently discovered to have excellent photocatalytic activity for dye degradation and alcohol oxidation. [148] The dye molecule was simpler to absorb owing to silica's hydrophilic characteristics. CTF-Th@SBA-15 has also shown effective catalytic activity of photocatalyst in solid as well as in metal-free mediums.…”

“…Furthermore, UPC‐CMP‐1 has a high selectivity for Congo red degradation when compared to a number of dyes for instance methyl orange, methyl red and Rhodamine B [147] . CTF‐Th@SBA‐15 is recently discovered to have excellent photocatalytic activity for dye degradation and alcohol oxidation [148] . The dye molecule was simpler to absorb owing to silica‘s hydrophilic characteristics.…”

Strategies to improve the photocatalytic performance of covalent triazine frameworks

“…Additionally, CTF-PTZ demonstrated efficient charge separation and transfer, yielding a signicant enhancement in the photocatalytic performance for the selective aerobic oxidation of suldes to sulfoxides. 94 Zhang et al synthesized D-A CTFs containing thiophene (Th), 96 diphenyl-thiophene (Th-Ph2) and diphenylbenzothiadiazole (BT-Ph2) 97 units directly on the surface of mesoporous silica (SBA-15). This approach aimed to combine the advantageous properties of both SBA-15 and D-A CTFs to form SBA-15-supported D-A CTF catalysts.…”

“…Zhang et al synthesized D–A CTFs containing thiophene (Th), 96 diphenyl-thiophene (Th-Ph2) and diphenyl-benzothiadiazole (BT-Ph2) 97 units directly on the surface of mesoporous silica (SBA-15). This approach aimed to combine the advantageous properties of both SBA-15 and D–A CTFs to form SBA-15-supported D–A CTF catalysts.…”

“…59 Furthermore, the combination of mesoporous silica with thiophene-containing CTFs yielded a composite material with a hexagonal cylinder morphology, which was utilized for the photodegradation of dyes in water. 96 The hydrophilic nature and high surface area of silica enhanced the adsorption of organic molecules, expanding the application of CTFs as photocatalysts for water treatment. Similarly, hollow nanoporous CTFs were synthesized using acid vapor-assisted solid-phase synthesis.…”