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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]

Functional thin films, being fabricated by incorporating discrete supramolecular architectures, have potential applications in research areas such as sensing, energy storage, catalysis, and optoelectronics. Here, we have determined that an anion‐coordinated triple helicate can be solution‐processed into a functional thin film by incorporation into a polymethyl methacrylate (PMMA) matrix. The thin films fabricated by the incorporation of the anion‐coordinated triple helicate show multiple optical properties, such as fluorescence, CD, and CPL. In addition, the film has the ability to recognize choline and choline derivatives in a water system. The successful recognition of Ch+ by the film represents the first example of utilizing 'aniono'‐supramolecular architectures for biomolecule detection in aqueous solution and opens up a new route for designing biocompatible functional materials. [ABSTRACT FROM AUTHOR]