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The semiconducting properties and applications of three dimensional (3D) covalent organic frameworks (COFs) are greatly hampered because of their long‐ranged non‐conjugated skeletons and relatively unstable linkages. Here, a robust imidazole‐linked fully conjugated 3D covalent organic framework (BUCT‐COF‐7) is synthesized through the one‐pot multicomponent Debus‐Radziszewski reaction of the saddle‐shaped aldehyde‐substituted cyclooctatetrathiophene, pyrene‐4,5,9,10‐tetraone, and ammonium acetate. The semiconducting BUCT‐COF‐7, as a metal‐free catalyst, shows excellent two electron oxygen reduction reaction (ORR) activity in alkaline medium with high hydrogen peroxide (H2O2) selectivity of 83.4 %. When the BUCT‐COF‐7 as cathode catalyst is assembled into the electrolyzer, the devices showed high electrochemical production rate of H2O2 up to 326.9 mmol g−1 h−1. The accumulative amount of H2O2 could totally degrade the dye methylene blue via Fenton reaction for wastewater treatment. This is the first report about intrinsic 3D COFs for efficient electrochemical synthesis of H2O2, revealing the promising applications of fully conjugated 3D COFs in the environment‐related field. [ABSTRACT FROM AUTHOR]

Two novel N‐doped nonalternant nanoribbons (NNNR‐1 and NNNR‐2) featuring multiple fused N‐heterocycles and bulky solubilizing groups were prepared via bottom‐up solution synthesis. NNNR‐2 achieves a total molecular length of 33.8 Å, which represents the longest soluble N‐doped nonalternant nanoribbon reported to date. The pentagon subunits and doping of N atoms in NNNR‐1 and NNNR‐2 have successfully regulated their electronic properties, achieving high electron affinity and good chemical stability enabled by the nonalternant conjugation and electronic effects. When applied a laser pulse of 532 nm, the 13‐rings nanoribbon NNNR‐2 shows outstanding nonlinear optical (NLO) responses, with the nonlinear extinction coefficient of 374 cm GW−1, much higher than those of NNNR‐1 (96 cm GW−1) and the well‐known NLO material C60 (153 cm GW−1). Our findings indicate that the N‐doping of nonalternant nanoribbons is an effective strategy to access another type of excellent material system for high‐performance NLO applications, which can be extended to construct numerous heteroatom‐doped nonalternant nanoribbons with fine‐tunable electronic properties. [ABSTRACT FROM AUTHOR]

Adhesives, Gels, Self-Assembly, Anion Coordination, Hydrogen Bonding Inside Back Cover: Hierarchical Self-Assembly of Adhesive and Conductive Gels with Anion-Coordinated Triple Helicate Junctions (Angew. Keywords: Adhesives; Anion Coordination; Gels; Hydrogen Bonding; Self-Assembly EN Adhesives Anion Coordination Gels Hydrogen Bonding Self-Assembly 1 1 1 05/18/22 20220523 NES 220523 B The hierarchical self-assembly b of functional gels with anion-coordinated architecture junctions will open up a new avenue for the design and fabrication of a broad range of smart materials. [Extracted from the article]