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Abstract A method for fabricating localized EC‐SERS probes based on nanopipettes and electrodeposition is described. Gold particles of fractal geometry with excellent SERS performance are produced, reliably and at low cost. By adapting the electrodeposition procedure, nanostructures of different sizes can be obtained, allowing the SERS platform to be tailored to many experimental configurations. In particular, by producing unique SERS platforms of dimensions comparable to the laser spot, quantitative comparison with electrochemical current is possible. By analyzing hundreds of samples, we thoroughly characterize the resulting geometry of the structures and their ability to enhance Raman signal, providing guidelines for the fabrication of optimized platforms. Control over the probes' surface potential also allows convenient modulation of surface‐analyte affinity and enable chemically unstable materials, such as Cu, to be reliably used. These are demonstrated by showing that Cu particles exposed to air can be easily re‐reduced, with no detriment in SERS performance. 

Abstract Chemical modification is a powerful strategy for tuning the electronic properties of 2D semiconductors. Here we report the electrophilic trifluoromethylation of 2D WSe₂and MoS₂under mild conditions using the reagent trifluoromethyl thianthrenium triflate (TTT). Chemical characterization and density functional theory calculations reveal that the trifluoromethyl groups bind covalently to surface chalcogen atoms as well as oxygen substitution sites. Trifluoromethylation induces p‐type doping in the underlying 2D material, enabling the modulation of charge transport and optical emission properties in WSe₂. This work introduces a versatile and efficient method for tailoring the optical and electronic properties of 2D transition metal dichalcogenides. 

Abstract A plasmonic nanolaser architecture that can produce white‐light emission is reported. A laser device is designed based on a mixed dye solution used as gain material sandwiched between two aluminum nanoparticle (NP) square lattices of different periodicities. The (±1, 0) and (±1, ±1) band‐edge surface lattice resonance (SLR) modes of one NP lattice and the (±1, 0) band‐edge mode of the other NP lattice function as nanocavity modes for red, blue, and green lasing respectively. From a single aluminum NP lattice, simultaneous red and blue lasing is realized from a binary dye solution, and the relative intensities of the two colors are controlled by the volume ratio of the dyes. Also, a laser device is constructed by sandwiching dye solutions between two Al NP lattices with different periodicities, which enables red–green and blue–green lasing. With a combination of three dyes as liquid gain, red, green, and blue lasing for a white‐light emission profile is realized. 

Abstract The recognition and separation of anions attracts attention from chemists, materials scientists, and engineers. Employing exo‐binding of artificial macrocycles to selectively recognize anions remains a challenge in supramolecular chemistry. We report the instantaneous co‐crystallization and concomitant co‐precipitation between [PtCl₆]²⁻dianions and cucurbit[6]uril, which relies on the selective recognition of these dianions through noncovalent bonding interactions on the outer surface of cucurbit[6]uril. The selective [PtCl₆]²⁻dianion recognition is driven by weak [Pt−Cl⋅⋅⋅H−C] hydrogen bonding and [Pt−Cl⋅⋅⋅C=O] ion–dipole interactions. The synthetic protocol is highly selective. Recognition is not observed in combinations between cucurbit[6]uril and six other Pt‐ and Pd‐ or Rh‐based chloride anions. We also demonstrated that cucurbit[6]uril is able to separate selectively [PtCl₆]²⁻dianions from a mixture of [PtCl₆]²⁻, [PdCl₄]²⁻, and [RhCl₆]³⁻anions. This protocol could be exploited to recover platinum from spent vehicular three‐way catalytic converters and other platinum‐bearing metal waste.