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Efficient and scalable production of high‐quality and processable two‐dimensional (2D) polymers are highly desired but have not yet been reported. Herein, we demonstrate a convenient noncovalent functionalization strategy for producing highly uniform, aqueous processable and semiconducting 2D triazine polymers. Experimental and theoretical analysis reveal that the aromatic amphiphilic 1‐pyrenebutyrate can adsorb and intercalate into the interlayer of bulk crystalline covalent triazine framework (CTF) through noncovalent π‐π stacking interaction between the pyrene moiety and the porous basal plane of 2D triazine polymer layer, which greatly facilitate the exfoliation of CTF in water in large scale. The as‐prepared highly water‐dispersible single‐layer/few‐layer 2D triazine polymer nanosheets can be easily processed into ultralight aerogels with a density of 5–15 mg cm−3, which can be further shaped into mechanically strong films upon simple compression. This noncovalent functionalization not only improve the dispersibility and processability of 2D triazine polymer, but also optimize its band structure and promote the photogenerated carrier separation via an interesting surface molecule doping effect, thus resulting in a remarkable photocatalytic hydrogen evolution rate of 1249 μmol h−1 (24980 μmol g−1 h−1) and apparent quantum efficiency up to 27.2 % at 420 nm for the 2D triazine polymer, outperforming most metal‐free photocatalysts ever reported. [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]

The rapid synthesis of crystalline covalent triazine frameworks (CTFs) and exploration of the polymerization mechanism are highly desired for the research of crystalline porous polymers, but have not yet been reported. Herein, we demonstrate a scalable microwave‐assisted synthetic strategy to successfully prepare a series of highly crystalline and semiconducting CTFs within 20 minutes for the first time. By in situ imaging and time‐dependent characterization, we proposed an ordered two‐dimensional (2D) polymerization mechanism for crystalline CTFs, in which the monomers rapidly polymerize into periodic 2D molecular sheets within 10 s and then grow into more ordered framework structures. Photocatalytic study of CTF with different crystallinity revealed that large crystalline domain could significantly improve the photocatalytic performance. Single‐layer and few‐layer crystalline 2D triazine polymer nanosheets could be obtained through simple ball‐milling exfoliation of the bulk layered CTFs and exhibit nearly fivefold improved photocatalytic hydrogen evolution rate up to 7971 μmol g−1 h−1. [ABSTRACT FROM AUTHOR]

In their Research Article (e202301865), Yuxi Xu et al. demonstrate that the obtained crystalline ultrathin 2D triazine polymer nanosheets can not only be assembled into ultralight and mechanically strong macroscopic porous aerogels, but also show a new surface molecule doping effect to significantly improve the photocatalytic water splitting activity. In their Research Article (e202301865), Yuxi Xu et al. demonstrate that the obtained crystalline ultrathin 2D triazine polymer nanosheets can not only be assembled into ultralight and mechanically strong macroscopic porous aerogels, but also show a new surface molecule doping effect to significantly improve the photocatalytic water splitting activity. Cover Picture: Aqueous Processable Two-Dimensional Triazine Polymers with Superior Photocatalytic Properties (Angew. [Extracted from the article]

Keywords: Antibiotic Removal; Covalent Triazine Framework; High Crystallinity; Kilogram-Scale Preparation; Polyphosphoric Acid Catalysis EN Antibiotic Removal Covalent Triazine Framework High Crystallinity Kilogram-Scale Preparation Polyphosphoric Acid Catalysis 1 1 1 06/14/22 20220620 NES 220620 B Kovalente organische Gerüstverbindungen b Eine allgemeine Strategie für die Herstellung von hoch kristallinen kovalenten organischen Gerüstverbindungen im Kilogrammmaßstab wird in der Zuschrift von Yuxi Xu et al. vorgestellt (e202203327). Frontispiz: A General Strategy for Kilogram-Scale Preparation of Highly Crystalline Covalent Triazine Frameworks Antibiotic Removal, Covalent Triazine Framework, High Crystallinity, Kilogram-Scale Preparation, Polyphosphoric Acid Catalysis. [Extracted from the article]

Back Cover: Rapid, Ordered Polymerization of Crystalline Semiconducting Covalent Triazine Frameworks (Angew. 2D ordered polymerization, 2D polymers, covalent triazine frameworks, large-scale synthesis, photocatalysis Keywords: 2D ordered polymerization; 2D polymers; covalent triazine frameworks; large-scale synthesis; photocatalysis EN 2D ordered polymerization 2D polymers covalent triazine frameworks large-scale synthesis photocatalysis 1 1 1 01/18/22 20220121 NES 220121 B The rapid synthesis b of crystalline semiconducting covalent triazine frameworks (CTFs) through a two-dimensional (2D) ordered polymerization mechanism is described by Yuxi Xu and co-workers in their Communication (e202113926). [Extracted from the article]

Rücktitelbild: Rapid, Ordered Polymerization of Crystalline Semiconducting Covalent Triazine Frameworks (Angew. 2D ordered polymerization, 2D polymers, covalent triazine frameworks, large-scale synthesis, photocatalysis Keywords: 2D ordered polymerization; 2D polymers; covalent triazine frameworks; large-scale synthesis; photocatalysis EN 2D ordered polymerization 2D polymers covalent triazine frameworks large-scale synthesis photocatalysis 1 1 1 01/18/22 20220121 NES 220121 B Die schnelle Synthese b von kristallinen halbleitenden kovalenten Triazin-Gerüststrukturen (CTFs) durch einen zweidimensionalen geordneten Polymerisationsmechanismus wird von Yuxi Xu et al. in ihrer Zuschrift demonstriert (e202113926). [Extracted from the article]

• Covalent triazine material was employed to passivate grain boundary defects. • The interaction between N and Pb2+ can fix the Pb2+ and reduce the lead leakage. • The electron-deficient triazine ring can fix I− through a anion-π interaction. • CTF-modified device obtained enhanced performances and stability. The grain boundary defects related non-radiative recombination, I− migration, and lead leakage problems are the foundational and fundamental aspects for the perovskite solar cells. Herein, covalent triazine frameworks (CTFs) are introduced into the perovskite film to address these problems. CTFs can passivate the uncoordinated Pb2+ defects at grain boundary and reduce the lead leakage based on the coordination interaction between nitrogen atoms in triazine ring and Pb2+. CTFs can also inhibit the I− migration and reduce the I− vacancy defects based on the anion-π interaction between electron-deficient triazine ring and I−. Benefited from the passivated grain boundary defects and inhibited I− migration by CTFs, the modified target device achieves a power conversion efficiency of 23.05 % with improved humidity stability and thermal stability. Therefore, this work lays the foundation for obtaining effective, stable, and environmentally friendly perovskite solar cells. [ABSTRACT FROM AUTHOR]