Nettles Charles B, Zhou Yadong, Zou Shengli, Zhang Dongmao
Department of Chemistry, Mississippi State University , Mississippi State, Mississippi 39762, United States.
Department of Chemistry, University of Central Florida , Orlando, Florida 32816, United States.
Anal Chem. 2016 Mar 1;88(5):2891-8. doi: 10.1021/acs.analchem.5b04722. Epub 2016 Feb 12.
Demonstrated herein is a UV-vis Ratiometric Resonance Synchronous Spectroscopic (R2S2, pronounced as "R-two-S-two" for simplicity) technique where the R2S2 spectrum is obtained by dividing the resonance synchronous spectrum of a NP-containing solution by the solvent resonance synchronous spectrum. Combined with conventional UV-vis measurements, this R2S2 method enables experimental quantification of the absolute optical cross sections for a wide range of molecular and nanoparticle (NP) materials that range optically from pure photon absorbers or scatterers to simultaneous photon absorbers and scatterers, simultaneous photon absorbers and emitters, and all the way to simultaneous photon absorbers, scatterers, and emitters in the UV-vis wavelength region. Example applications of this R2S2 method were demonstrated for quantifying the Rayleigh scattering cross sections of solvents including water and toluene, absorption and resonance light scattering cross sections for plasmonic gold nanoparticles, and absorption, scattering, and on-resonance fluorescence cross sections for semiconductor quantum dots (Qdots). On-resonance fluorescence quantum yields were quantified for the model molecular fluorophore Eosin Y and fluorescent Qdots CdSe and CdSe/ZnS. The insights and methodology presented in this work should be of broad significance in physical and biological science research that involves photon/matter interactions.
本文展示了一种紫外可见比率共振同步光谱（R2S2，为简便起见发音为“R-two-S-two”）技术，其中R2S2光谱是通过将含纳米颗粒溶液的共振同步光谱除以溶剂共振同步光谱获得的。结合传统的紫外可见测量，这种R2S2方法能够对多种分子和纳米颗粒（NP）材料的绝对光学截面进行实验量化，这些材料在紫外可见波长区域的光学性质范围从纯光子吸收体或散射体到同时具备光子吸收、散射、发射功能的物质，涵盖了从仅吸收光子或散射光子到同时吸收、散射和发射光子的所有情况。该R2S2方法的示例应用包括量化水和甲苯等溶剂的瑞利散射截面、等离子体金纳米颗粒的吸收和共振光散射截面，以及半导体量子点（Qdots）的吸收、散射和共振荧光截面。对模型分子荧光团曙红Y以及荧光量子点CdSe和CdSe/ZnS的共振荧光量子产率进行了量化。本文所展示的见解和方法在涉及光子/物质相互作用的物理和生物科学研究中应具有广泛的意义。
