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A persistent challenge in utilizing Au nanocrystals for surface‐enhanced Raman spectroscopy (SERS) lies in achieving controllable superstructures that maximize SERS performance. Here, a novel strategy is proposed to enhance the SERS performance by precisely adjusting the tip arrangements of Au nanobipyramids (BPs) in two‐dimensional (2D) superlattices (SLs). This is achieved through ligand‐exchange of Au BPs, followed by liquid‐air interfacial assembly, resulting in large‐area, transferrable SL membranes. The key to controlling the arrangement of Au BPs in the SLs is the regulation of the amount of free ligands added during self‐assembly, which allows for the precise formation of various configurations such as tilted SLs, tip‐on‐tip SLs, and tip‐to‐tip SLs. Among these configurations, tip‐on‐tip SLs exhibit the highest enhancement factor for SERS, reaching an impressive value of 1.95×108, with uniform and consistent SERS signals across a large area. The experimental findings are further corroborated by simulations using the finite element method. This study establishes an efficient method for engineering the microstructure of 2D SLs composed of Au BPs, highlighting the importance of fine‐tuning the tip arrangements of Au BPs to regulate SERS performance. [ABSTRACT FROM AUTHOR]

The fabrication of anion‐coordinated assemblies into functional soft materials remains a major challenge. To this end, four C2‐symmetric anion‐binding ligands equipped with ortho‐phenylene‐bridged bis(urea) and amine or amide ends were designed, which generated A2L3 triple helical architectures upon self‐assembly with phosphate ions. Hierarchical intermolecular hydrogen bonds among the terminal amine/amide groups and urea moieties resulted in the formation of functional gels. The obtained gels were further applied for conductive adhesion between different surfaces, displaying excellent flexibility and selective wettability. The viscoelastic gels constructed from anion‐coordinated assemblies described in this work represent the first example of a new class of anion‐coordination‐driven smart materials. [ABSTRACT FROM AUTHOR]

Adhesives, Gels, Hydrogen Bonding, Self-Assembly, Anion Coordination Innenrücktitelbild: 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 Die hierarchische Selbstorganisation b von funktionellen Gelen mit anionenkoordinierten Architekturen eröffnet eine neue Strategie für die Entwicklung und Herstellung intelligenter Materialien. [Extracted from the article]