Photonics and Optoelectronics Group and CeNS, Department of Physics, Ludwig-Maximilians Universität München, 80799 München, Germany.
Nano Lett. 2012 Mar 14;12(3):1247-52. doi: 10.1021/nl203673g. Epub 2012 Feb 21.
Unbiased gold nanoparticles are negatively charged in aqueous solution but not hydrated. Optical spectroscopy of voltage-clamped single gold nanoparticles reveals evidence that anion adsorption starts at positive potentials above the point of zero charge, causing severe but reversible plasmon damping in combination with a spectral red shift exceeding the linear double layer charging effect. Plasmon damping by adsorbate is relevant for the use of nanoparticles in catalysis, in biodiagnostics, and in surface enhanced Raman scattering.
在水溶液中，中性的金纳米颗粒带负电荷但不带水合层。对电压钳制的单个金纳米颗粒的光学光谱研究表明，在零电荷点以上的正电势下，阴离子吸附开始，导致严重但可恢复的等离子体阻尼，同时伴有超过线性双层充电效应的光谱红移。吸附物对等离子体的阻尼在纳米颗粒的催化、生物诊断和表面增强拉曼散射的应用中是相关的。
