We report on the near-field imaging of microstructured polymer layers deposited on an homogeneous metal thin film on which a surface plasmon mode is excited. The microstructures in the polymer layers are designed by electron beam lithography, and the near-field imaging is performed with a photon scanning tunneling microscope (PSTM). We show that, despite their very small height, the microstructures can be conveniently imaged with a PSTM thanks to the field enhancement at the surface of the metal thin film supporting the surface plasmon. The influence of the illumination conditions on the contrast of the PSTM images is discussed. In particular, we show that both the field enhancement and the near-field intensity distribution around the microstructures depend dramatically upon the illumination conditions, leading to the conclusion that the PSTM is well suited for spatially resolved near-field surface plasmon sensing purposes.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/la048242q | DOI Listing |
Chem Asian J
January 2025
Universidad Austral de Chile, Instituto de Ciencias Químicas, CHILE.
Plasmonic materials can be utilized as effective platforms to enhance luminescent signals of luminescent metal nanoclusters (LMNCs). Both surface enhanced fluorescence (SEF) and shell-isolated nanoparticle-enhanced fluorescence (SHINEF) strategies take advantage of the localized and increased external electric field created around the plasmonic metal surface when excited at or near their characteristic plasmonic resonance. In this context, we present an experimental and computational study of different plasmonic composites, (Ag) Ag@SiO2 and (Au) Au@SiO2 nanoparticles, which were used to enhance the luminescent signal of Au nanoclusters coated with glutathione (GSH) molecule (Au25GSH NCs).
View Article and Find Full Text PDFSensors (Basel)
December 2024
Institute of Fundamental Technological Research, Polish Academy of Sciences, ul. Pawińskiego 5B, 02-106 Warsaw, Poland.
In this paper, we demonstrate that torsional surface elastic waves can propagate along the curved surface of a metamaterial elastic rod (cylinder) embedded in a conventional elastic medium. The crucial parameter of the metamaterial rod is its elastic compliance s44(1)ω, which varies as a function of frequency ω analogously to the dielectric function εω in Drude's model of metals. As a consequence, the elastic compliance s44(1)ω can take negative values s44(1)ω<0 as a function of frequency ω.
View Article and Find Full Text PDFSensors (Basel)
December 2024
Center for Experimental Chemistry Education of Shandong University, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
In this study, a simple and easy synthesis strategy to realize the modification of AuHgPt nanoalloy materials on the surface of ITO glass at room temperature is presented. Gold nanoparticles as templates were obtained by electrochemical deposition, mercury was introduced as an intermediate to form an amalgam, and then a galvanic replacement reaction was utilized to successfully prepare gold-mercury-platinum (AuHgPt) nanoalloys. The obtained alloys were characterized by scanning electron microscopy, UV-Vis spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction techniques.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Hainan Engineering Research Center of Tropical Ocean Advanced Opto-Electrical Functional Materials, College of Chemistry and Chemical Engineering, Hainan Normal University, Haikou 571158, China.
Chrysoidin (CG) can be ingested into the human body through the skin and cause chronic toxicity, so the detection of CG levels in the environment is crucial. In this study, we synthesize F-Ag@ZIF-8/PVC molecular-imprinted membranes (FZAP-MIM) by an innovative combination of SERS detection, membrane separation, and a molecular-imprinted technique in order to perform the analysis of CG in water. The plasmonic MOF material as a SERS substrate helps to enrich the target and realize the spatial overlap of the target with the nanoparticle tip "hotspot".
View Article and Find Full Text PDFMolecules
January 2025
Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical Engineering and New Phosphorus Materials, Yunnan International Joint Laboratory of Sustainable Polymers, The Higher Educational Key Laboratory for Phosphorus Chemical Engineering of Yunnan Province, Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming 650500, China.
The growing demand for sustainable energy storage solutions has underscored the importance of phase change materials (PCMs) for thermal energy management. However, traditional PCMs are always inherently constrained by issues such as leakage, poor thermal conductivity, and lack of solar energy conversion capacity. Herein, a multifunctional composite phase change material (CPCM) is developed using a balsa-derived morphology genetic scaffold, engineered via bionic catechol surface chemistry.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!