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The ability to molecularly engineer materials is a powerful tool toward increasingly performing heterogeneous catalysts. Porous organic polymers stand out as photocatalysts due to their high chemical stability, outstanding optoelectronic properties and their easy and tunable syntheses. In photocatalysis, the insertion of photosensitizing π‐extended molecules into molecularly well‐defined donor‐acceptor junctions is supposed to increase the catalytic activity, but yet remain experimentally underdeveloped. This study presents a pyrene‐based Covalent Triazine Framework (CTF) synthesized through a polycondensation approach, which was designed to contain a molecularly‐defined pyrene‐triazine‐bipyridine donor‐acceptor‐acceptor triad as the repetition unit of the CTF. The CTF is an efficient photocatalyst for hydrogen evolution from water reaching a significant production rate of 61.5 mmolH2/h/gcat. Moreover, the same CTF can easily be used as porous macroligand for an organometallic Rh complex to efficiently catalyze the carbon dioxide photoreduction into formic acid under visible light. [ABSTRACT FROM AUTHOR]

We have synthesized a new hybrid material, Ag0@CTFN in which small-sized Ag-nanoparticles (Ag-NPs) are anchored on the surface of covalent triazine framework nanosheet (CTFN). Here, CTFN works as the support as well as the capping agent for the small-sized Ag-NPs. Ag0@CTFN has been synthesized in a one pot method where Ag-NPs attach with the nitrogen atoms present in the triazin units. This as synthesized Ag0@CTFN material has been characterized by FTIR, XRD, N 2 adsorption desorption analysis, SEM, TEM and XPS analysis. All these characterizations reveal that around 4.97 nm sized Ag-NPs are anchored on the surfaces of layer-like CTFN nanosheets. Ag0@CTFN samples have shown their excellent catalytic activity for the selectively oxazolidinone formation from propargyl alcohol and amine by fixing CO 2 under mild reaction condition. Moreover, this is the first report on Ag0@CTFN hybrid material which catalyze the oxazolidinone synthesis by fixing CO 2. Again, this catalyst has shown their recyclability for oxazolidinone synthesis reaction up to sixth cycle by keeping their activity almost intact. There is no metal or catalyst leaching noticed up to sixth cycle for this reaction. AgNPs decorated Porous polymeric framework was constructed and employed as an efficient reusable heterogeneous catalyst for the synthesis of oxazolidinone from propargyl alcohol and amines by fixing CO 2 under very mild reaction conditions. [Display omitted] • We have synthesized Ag0@CTFN, in which small-sized Ag-nanoparticles are anchored on the surface of covalent triazine framework nanosheet (CTFN). Here, CTFN works as the support as well as the capping agent for the small-sized Ag-NPs. • Moreover, this is the first report in which small-sized Ag-nanoparticles (Ag-NPs) are anchored on the surface of covalent triazine framework nanosheet (CTFN). • The hybrid material, Ag0@CTFN was characterized by FTIR, PXRD, SEM, TEM, N 2 -adsorption desorption, XPS analysis. • The Ag0@CTFN samples showed excellent catalytic activity for the selectively oxazolidinone formation from propargyl alcohol and amine by fixing CO 2 under mild reaction condition. • This Ag0@CTFN acts as a heterogeneous catalyst that can be easily separated from the reaction mixture for reuse. [ABSTRACT FROM AUTHOR]

[Display omitted] • Naphthalene-based COFs are used to support Pd nanoparticles. • COF-supported Pd nanoparticles have a small size of 1.2 ± 0.3 nm. • COF-supported Pd nanoparticles show good catalytic performance in formic acid dehydrogenation for generating hydrogen. • COF-supported Pd nanoparticles exhibit good stability. Formic acid (FA) is considered as a kind of promising hydrogen storage materials due to its economic feasibility, safety, stability and high hydrogen density. Nevertheless, it is a challenge to design a high-performance catalyst with high activity, selectivity and stability for the dehydrogenation of FA to generate hydrogen (H 2). Herein, a range of covalent triazine frameworks (CTFs including 1,8-CTF, 1,5-CTF and 2,3-CTF) with abundant nitrogen atoms are developed to support palladium nanoparticles for efficiently catalyzing FA dehydrogenation. Ultrasmall palladium nanoparticles with a size of 1.2 ± 0.3 nm showed near 100 % H 2 selectivity and high catalytic activity in FA dehydrogenation supported by 1,8-CTF. The activation energy of FA dehydrogenation catalyzed by Pd/1,8-CTF reaches 26.17 kJ·mol−1. In addition, Pd/1,8-CTF exhibits high stability and easy recyclability, and the catalytic activity is maintained even after 6 cycles. This work gives a feasible strategy to develop high-efficiency and selective nanocatalysts for H 2 production from FA dehydrogenation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The first example of covalent triazine frameworks derived from biomass was designed and synthesized. • Heterogeneous catalyst Cp*Ir@CTF-biomass and its homogeneous analog have approximate catalytic activity. • Catalytic activity of Cp*Ir@CTF-biomass is well maintained during six runs. The first example of covalent triazine frameworks derived from biomass was designed and synthesized. Furthermore, an iridium complex Cp*Ir@CTF-biomass was prepared by the coordinative immobilization of [Cp*IrCl 2 ] 2 on the synthesized covalent triazine framework. In the presence of Cp*Ir@CTF-biomass (0.03 mol % Ir), the reaction was carried out for 24 min at 80 °C and an almost complete dehydrogenation of formic acid with an initial TOF of 7627 h−1 was observed. Further experiments confirmed that heterogeneous catalyst Cp*Ir@CTF-biomass and its homogeneous analog [Cp*Ir(pyridine)Cl 2 ] have approximate catalytic activity. Moreover, catalytic activity of Cp*Ir@CTF-biomass is well maintained during six runs. ©2024 Elsevier Inc. All rights reserved. [ABSTRACT FROM AUTHOR]

Scalable and eco‐friendly synthesis of crystalline porous covalent triazine frameworks (CTFs) is essential to realize their broad industrial applications but remains a great challenge, which requires the fundamental understanding of the two‐dimensional polymerization mechanism. Herein, we report a universal polyphosphoric acid (H6P4O13)‐catalyzed nitrile trimerization route to synthesize a series of highly crystalline CTFs with high specific surface areas. This new strategy enables the cost‐effective large‐scale fabrication of crystalline CTFs at kilogram level for the first time. Through density functional theory calculation and detailed controlled experiments, we reveal that the polyphosphate acid show much higher catalytic activity for trimerization reaction than its analogues such as P2O5 and H3PO4. Furthermore, the crystalline CTFs with regular porosity and abundant triazine groups exhibit ultrahigh removal efficiency of micropollutants, indicating its great potential in environment remediation. [ABSTRACT FROM AUTHOR]

A template-free pyrolysis approach is proposed to fabricate nitrogen and sulfur doped hollow mesoporous carbon sphere (N/S-HMCS). The unique hollow/mesoporous nanostructure and abundant N, S-doped active sites prompt the optimal N/S-HMCS 900 exhibits satisfactory electrocatalysis in oxygen electroreduction for high-performance Zn-air battery. [Display omitted] • A nitrogen, sulfur dual-doped hollow mesoporous carbon sphere (N/S-HMCS) is fabricated by a simple yet efficient template-free pyrolysis approach. • The N/S-HMCS 900 exhibits high oxygen reduction reaction (ORR) activities with an excellent half-wave potential and high methanol tolerance. • The optimal electrocatalyst can be used as air electrode materials in high-performance zinc-air batteries. • Density functional theory (DFT) calculations reveal that N, S-dual dopant can create extra active sites with higher catalytic activity than the isolated N -dopant. The construction of hollow mesoporous carbon nanospheres (HMCS) avoiding the use of traditional soft/hard templates is highly desired for nanoscience yet challenging. Herein, we report a simple and straightforward template-free strategy for preparing nitrogen, sulfur dual-doped HMCSs (N/S-HMCSs) as oxygen reduction reaction (ORR) electrocatalysts. The unique hollow spherical and mesoporous structure was in-situ formed via a thermally initiated hollowing pathway from an elaborately engineered covalent triazine framework. Regulation of pyrolysis temperatures contributed to precisely tailoring of the shell thickness of HMCSs. The resulting N/S-HMCS 900 (pyrolyzed at 900 °C) possessed high N and S contents, large specific surface areas, rich and uniform mesopores distribution. Consequently, as a metal-free ORR electrocatalyst, N/S-HMCS 900 exhibits a high half-wave potential, excellent methanol tolerance and great long-term durability. Additionally, density functional theory calculations demonstrate that N, S-dual dopant can create extra active sites with higher catalytic activity than the isolated N -dopant. This strategy provides new insights into the construction of hollow and mesoporous multi-heteroatom-doped carbon materials with tunable nanoarchitecture for various electrochemical applications. [ABSTRACT FROM AUTHOR]

The synthesis of novel porous polymeric materials with active coordinating motifs is one of the most interesting topics in the field of heterogeneous catalysis and materials chemistry. This study adopts a post-modification strategy to construct three CuI-modified covalent triazine frameworks with different micropores. Bipyridine coordination sites are formed in the porous polymeric structures when the monomers are polymerized into covalent triazine frameworks. Cuprous iodide is uploaded into the skeleton via Cu–N/Cu–I cooperative coordination and forms a metal catalytic site. Furthermore, the uniformly anchored [(N^N) CuI] metal catalytic site donates CTFs to catalyze the azide-alkyne cycloaddition reaction in an aqueous solution, with high efficiency, excellent tolerance (>70% isolated yield for seven examples), and good recyclability, at room temperature. Three CuI-functionalized covalent triazine frameworks (CuI-CTFs) with different pore sizes were stepwise constructed via trimerization reaction and mild post-synthetic modification with copper iodide. These water-stable CuI-based porous polymeric catalysts exhibited highly heterogenous catalysis activity to CuAAC reaction under mild condition. [Display omitted] • Three CuI-CTFs with different pore sizes were post-synthesized via trimerization reaction and metal coordination. • Such Cu(I)-based CTF S exhibited excellent catalytic activity to CuAAC reaction in aqueous. • These CuI-doped CTFs catalysts can be reused in many times without remarkable deactivation. [ABSTRACT FROM AUTHOR]

[Display omitted] • CTF with Fe incorporation was used to prepare a series of Fe/TTF electrocatalysts. • Fe/TTF-0.5-900 exhibited the optimal catalytic activity in ORR process. • The MPD of MFC with Fe/TTF-0.5-900 cathode reached up to 2617 mW·m−2. • DFT confirmed that Fe 3 C accelerated the break of O-O bond in *OOH. The low power output of microbial fuel cell (MFC) requires high-performance catalysts to facilitate cathodic oxygen reduction reaction (ORR). In this work, a series of electrocatalysts (Fe/TTF) are synthesized by thermalizing N-rich covalent triazine framework (CTF) with various amount of FeCl 3 ·6H 2 O at different calcination temperatures for ORR catalysis in MFC. Electrochemical measurements reveal that Fe/TTF-0.5-900 synthesized with a mass ratio of 1:2 (FeCl 3 ·6H 2 O: CTF) at 900 °C exhibits the minimum charge transfer resistance and optimal catalytic behavior in ORR process. The MFC with Fe/TTF-0.5-900 cathode displays a high maximum power density of 2617 mW·m−2, which surpasses those of other Fe/TTF electrocatalysts, thermalized covalent triazine framework (TTF) and the benchmark activated carbon (AC). The results indicate that TTF as a porous carbon matrix with favorable nitrogen doping promotes charge and mass transfer greatly, and the combination of iron carbide substantially benefits the improvement of MFC performance. Moreover, according to density functional theory (DFT) calculation, iron carbide is significantly preferable for ORR catalysis by accelerating the break of O-O bond in *OOH, which further reveals that the ORR on iron carbide follows four-electron pathway. Therefore, Fe/TTF-0.5-900 can be applied as an economical and highly active electrocatalyst in MFC to achieve high-efficiency energy conversion. [ABSTRACT FROM AUTHOR]