Surface plasmon resonance

About: Surface plasmon resonance is a research topic. Over the lifetime, 24909 publications have been published within this topic receiving 810976 citations. The topic is also known as: Surface plasmon resonance & SPR (technology).

Phosphorus-doped silicon nanocrystals exhibiting mid-infrared localized surface plasmon resonance.

Abstract: Localized surface plasmon resonances (LSPRs) enable tailoring of the optical response of nanomaterials through their free carrier concentration, morphology, and dielectric environment. Recent efforts to expand the spectral range of usable LSPR frequencies into the infrared successfully demonstrated LSPRs in doped semiconductor nanocrystals. Despite silicon’s importance for electronic and photonic applications, no LSPRs have been reported for doped silicon nanocrystals. Here we demonstrate doped silicon nanocrystals synthesized via a nonthermal plasma technique that exhibits tunable LSPRs in the energy range of 0.07–0.3 eV or mid-infrared wavenumbers of 600–2500 cm–1.

Poly(vinyl alcohol) capped silver nanoparticles as localized surface plasmon resonance-based hydrogen peroxide sensor

Abstract: A colorimetric hydrogen peroxide sensor based on localized surface plasmon resonance of poly(vinyl alcohol) capped silver nanoparticles is introduced. The silver nanoparticles are directly synthesized in the PVA matrix by a one-step method based on the reduction of the inorganic precursor AgNO3 through thermal treatment in aqueous medium. No other reagent is used. These nanoparticles are characterized using UV–vis spectroscopy, transmission electron microscopy and X-ray diffraction. Then they are used for the preparation, characterization and calibration of a highly sensitive, cost-effective and renewable localized surface plasmon resonance-based hydrogen peroxide sensor. The silver nanoparticles have the catalytic ability for the decomposition of hydrogen peroxide; then the decomposition of hydrogen peroxide induces the degradation of silver nanoparticles. Hence, a remarkable change in the localized surface plasmon resonance absorbance strength could be observed. As a result, the yellow colour of the silver nanoparticle–polymer solution was gradually changed to transparent colour. Furthermore, when this transparent solution was subjected to thermal treatment, it became again yellow and the UV–vis spectroscopy confirmed that nanoparticles were again formed, suggesting the renewability of this sensor. The determination of reactive oxygen species such as hydrogen peroxide has possibilities for applying to medical and environmental applications.

Versatile Solution Phase Triangular Silver Nanoplates for Highly Sensitive Plasmon Resonance Sensing

Abstract: Solution phase triangular silver nanoplates (TSNP) with versatile tunability throughout the visible-NIR wavelengths are presented as highly sensitive localized surface plasmon refractive index sensors. A range of 20 TSNP solutions with edge lengths ranging from 11 to 200 nm and aspect ratios from 2 to 13 have been studied comprehensively using AFM, TEM, and UV-vis-NIR spectroscopy. Studies of the localized surface plasmon resonance (LSPR) peak's sensitivity to refractive index changes are performed using a simple sucrose concentration method whereby the surrounding refractive index can solely be changed without variation in any other parameter. The dependence of the TSNP localized surface plasmon resonance (LSPR) peak wavelength lambda(max) and its bulk refractive index sensitivity on the nanoplate's structure is determined. LSPR sensitivities are observed to increase linearly with lambda(max) up to 800 nm, with the values lying within the upper limit theoretically predicted for optimal sensitivity, notwithstanding any diminution due to ensemble averaging. A nonlinear increase in sensitivity is apparent at wavelengths within the NIR region with values reaching 1096 nm.RIU(-1) at lambda(max) 1093 nm. Theoretical studies performed using a simple aspect ratio dependent approximation method and discrete dipole approximation methods confirm the dependence of the LSPR bulk refractive index sensitivity upon the TSNP aspect ratio measured experimentally. These studies highlight the importance of this key parameter in acquiring such high sensitivities and promote these TSNP sols for sensing applications at appropriate wavelengths for biological samples.