Plasmonic nanoparticles at the periphery of poly(4-vinylpyridine) shell in core@shell nanostructures for localized surface plasmon resonance-based sensing and electrocatalysis = Plasmonic nanoparticles at the periphery of poly(4-vinylpyridine) shell in core@shell nanostructures for localized surface plasmon resonance-based sensing and electrocatalysis

다국어 초록 (Multilingual Abstract)

Bimetallic Core@shell nanoparticles have demonstrated distinctly different properties and potential uses in electronics, magnetics, catalysts, optics, and sensors. Their versatility in a wide range of applications stems from their unique physical and chemical properties directly related to particle size, shape, and interparticle distance and surface properties. The unique properties of the gold nanoparticles (AuNPs) are originated from the localized surface plasmon resonance (LSPR) phenomenon, the coupling of light into the resonant oscillation of charge density on the nanostructured noble metal surface. Core@shell type nanospheres have also been utilized as a platform for integration of functionalities into both the core and shell. The interaction between two types of metal NPs selectively located in the core and shell may alter the LSPR property, depending on the relative amount of the two metal components, the relative distance between them and the shell thickness. We suggest a unique strategy to generate core@shell nanoparticles based on pH-sensitive AuNPs decorated with polymer shell. Concretely, pH-sensitive AuNPs having P4VP on the surface were first fabricated through SI-ATRP. Then, they were mixed with selected metal precursor solutions followed by reduction using reducing agent. The metal NPs thus incorporated were distributed uniformly in the P4VP polymer shells. We investigate the structural change during the sequential synthetic process. The bimetallic nanostructures of AuNP@P4VP nanocomposites containing another type of metal NP at the P4VP periphery exhibit a controlled sensing property in terms of the change in the refractive index of surrounding media and a typical electrocatalytic activity for methanol oxidation reaction.