Covalent Triazine‐Based Frameworks as Visible Light Photocatalysts for the Splitting of Water

Abstract

Covalent triazine-based frameworks (CTFs) with a graphene-like layered morphology have been controllably synthesized by the trifluoromethanesulfonic acid-catalyzed nitrile trimerization reactions at room temperature via selecting different monomers. Platinum nanoparticles are well dispersed in CTF-T1, which is ascribed to the synergistic effects of the coordination of triazine moieties and the nanoscale confinement effect of CTFs. CTF-T1 exhibits excellent photocatalytic activity and stability for H2 evolution in the presence of platinum under visible light irradiation (λ ≥ 420 nm). The activity and stability of CTF-T1 are comparable to those of g-C3 N4 . Importantly, as a result of the tailorable electronic and spatial structures of CTFs that can be achieved through the judicial selection of monomers, CTFs not only show great potential as organic semiconductor for photocatalysis but also may provide a molecular-level understanding of the inherent heterogeneous photocatalysis.

A Covalent Triazine‐Based Framework Consisting of Donor–Acceptor Dyads for Visible‐Light‐Driven Photocatalytic CO2 Reduction

“…In contrastt ob lack CTFs prepared by ZnCl 2 -catalyzed cyclotrimerizationo fc yano-containing aromatic building blocks, [17] DA-CTF prepared by acid-catalyzed reaction is yellow (inset in Figure 2a). The bandgapo fD A-CTF from UV/Vis DRS was 2.35 eV (Figure 2b), which was narrower than that of CTF-T1 (2.94 eV) [18] and reportedc ovalento r- ganic frameworks. Am aximum absorption peak at 400-550 nm was assigned to the p-p*t ransitions of the conjugated aromatic frameworks.…”

“…[16b] These results demonstrated that DA-CTF holds great promise for the application in CO 2 catalytic conversion. Compared with the light-harvesting efficiency of CTF-T1 prepared from 1,4-dicyanobenzene, [18] the enhanced light absorption of DA-CTF was most likely owing to the introductiono ft he electron-donating triphenylamine group. The UV/ Vis diffuse-reflectance spectrum (UV/Vis DRS) of DA-CTF contained ab road absorption band up to 700 nm;t he addition of 2,2'-bipyridine and Co 2 + had no effecto nt he absorption of DA-CTF (Figure 2a).…”

Pore Surface Engineering of Covalent Triazine Frameworks@MoS2 Electrocatalyst for the Hydrogen Evolution Reaction

“…[27] Meanwhile, interplanars pacing of 0.27 nm is in accordance with the (1 00) Based on the above,C TFs@MoS 2 -X have ac rystal p-conjugated stacking architecture and hierarchical meso-and micropores in one hybrid system;t his fine structure is facile for fast p-electron hopping,m ass transfer,a nd confinement of the MoS 2 nanoparticles to facilitate large-particle growth. [38] The electrocatalytic performance of as-synthesized CTFs, free MoS 2 ,C TFs@MoS 2 -X, and commercial 20 %P t/C catalysts were evaluated and compared using linear sweep voltammograms (LSV) in 0.5 m H 2 SO 4 solution (N 2 saturated) with at ypical three-electrode system (Figure 4). [28][29][30][31][32][33][34][35] The nitrogen-containing triazine unit in the CTF skeleton can activate the electrons around the carbon,w hich will lead to an outstanding electrochemical performance.…”

Conjugated Polymers: Catalysts for Photocatalytic Hydrogen Evolution

“…[38] By controlling the structure of the monomers,s uch as introduction of methyl groups,t he optical and electronic properties of the polymers could be manipulated. [38] By controlling the structure of the monomers,s uch as introduction of methyl groups,t he optical and electronic properties of the polymers could be manipulated.…”