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Covalent triazine frameworks (CTFs) are normally synthesized by ionothermal methods.T he harsh synthetic conditions and associated limited structural diversity do not benefit for further development and practical large-scale synthesis of CTFs.Herein we report anew strategy to construct CTFs (CTF-HUSTs) via apolycondensation approach,which allows the synthesis of CTFs under mild conditions from aw ide arrayo fb uilding blocks.I nterestingly,t hese CTFs displayalayered structure.T he CTFs synthesized were also readily scaled up to gram quantities.T he CTFs are potential candidates for separations,p hotocatalysis and for energy storage applications.I np articular,C TF-HUSTs are found to be promising photocatalysts for sacrificial photocatalytic hydrogen evolution with am aximum rate of 2647 mmol h À1 g À1 under visible light. We also applied ap yro-lyzed form of CTF-HUST-4 as an anode material in asodium-ion battery achieving an excellent discharge capacity of 467 mAh g À1. Covalent organic frameworks (COFs) are an emerging class of porous materials,characterized by their ordered structures, high surface areas,and structural diversity. [1] They have shown promise in applications such as gas adsorption, [2] catalysis, [3] and optoelectronics. [4] Av ariety of methods have been reported to prepare COFs,s uch as polycondensation, [1a, 4a] cyclization reactions, [5] or surface mediated methods. [1b, 6] Covalent triazine frameworks (CTFs) are related to COFs and are typically constructed through cyclization reaction of nitrile aromatic building blocks;t hey feature high physico-chemical stability and high nitrogen content. [5, 7] Because of these characteristics,CTFs have found diverse applications in gas adsorption and storage, [5a, 7a,b] catalysis, [7c-e] and energy storage. [7f,g] There are still, however, al imited number of approaches for the synthesis of CTFs. [5a, 7a] Themost common approach is ionothermal synthesis at high temperatures (! 400 8 8C), which also requires alarge amount of ZnCl 2 to serve as both catalyst and reaction medium. [5a] This method can lead to CTFs with ad egree of crystalline order,b ut the high reaction temperatures cause the partial carbonization of the structure and the materials are obtained in the form of black powders.H ence,C TFs prepared by this method lack an electronic band gap and may be unsuitable for photophysical applications.F urthermore,t hese reaction temperatures consume alarge amount of energy and preclude all but the most stable building blocks,thus limiting the scope for scale up and synthetic diversity.I ti s, therefore,i mperative to find new methods for the synthesis of CTFs under milder conditions. Previous research has shown that CTFs could be synthesized at room temperature,a nd catalyzed by strong and corrosive acid such as trifluoromethylsufonic acid. [7a,b] This avoids carbonization, but the method is obviously not suitable to acid-sensitive building blocks,and also the resulting materials did not have layered structures. Here,wedevelop anew strategy involvi...

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A range of conjugated microporous polymer networks has been prepared using Sonogashira-Hagihara cross-coupling of 1,3,5-triethynylbenzene with a number of functionalized dibromobenzenes. Porous poly(arylene ethynylene) networks with surface areas up to 900 m2/g were produced. The surface chemistry of the networks was varied by monomer selection, thus allowing control over physical properties such as hydrophobicity. Additionally, it was shown that the dye sorption behavior of the networks can be controlled by varying the hydrophobicity. This expands significantly on the utility of this approach, allowing high surface area networks to be prepared with properties that can be tailored for applications such as catalysis and separations