Liu Bi-Ju, Lin Kai-Qiang, Hu Shu, Wang Xiang, Lei Zhi-Chao, Lin Hai-Xin, Ren Bin
State Key Laboratory of Physical Chemistry of Solid Surfaces, ‡The MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, and §Collaborative Innovation Center of Chemistry for Energy Materials, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China.
Anal Chem. 2015 Jan 20;87(2):1058-65. doi: 10.1021/ac503612b. Epub 2014 Dec 29.
Noble metal nanoparticles have unique localized surface plasmon resonance (LSPR), leading to their strong absorption and scattering in the visible light range. Up to date, the common practice in the selection of nanoparticles for a specific application is still based on the measured extinction spectra. This practice may be erroneous, because the extinction spectra contain both absorption and scattering contribution that may play different roles in different applications. It would be highly desirable to develop an efficient way to obtain the absorption and scattering spectra simultaneously. Herein, we develop a method to use the experimentally measured extinction and scattering signals to extract the absorption and scattering spectra that is in excellent agreement with that simulated by discrete dipole approximation (DDA). The heating curve measurement on the three types of gold nanorods, with almost the same extinction spectra but different absorption and scattering contribution, convincingly reveals an excellent correlation between the heating effect and the absorption strength rather than the extinction strength. The result demonstrates the importance to obtain the scattering and absorption spectra to predict the potential application for different types of nanoparticles, which in turn will screen efficiently nanoparticles for a specific application.
贵金属纳米颗粒具有独特的局域表面等离子体共振（LSPR），使其在可见光范围内具有强烈的吸收和散射。迄今为止，针对特定应用选择纳米颗粒的常见做法仍基于测量的消光光谱。这种做法可能是错误的，因为消光光谱包含吸收和散射贡献，而它们在不同应用中可能发挥不同作用。非常希望开发一种有效方法来同时获得吸收光谱和散射光谱。在此，我们开发了一种方法，利用实验测量的消光和散射信号来提取吸收光谱和散射光谱，该方法与离散偶极近似（DDA）模拟的结果高度吻合。对三种具有几乎相同消光光谱但吸收和散射贡献不同的金纳米棒进行的加热曲线测量，令人信服地揭示了加热效应与吸收强度而非消光强度之间的良好相关性。结果表明，获得散射光谱和吸收光谱对于预测不同类型纳米颗粒的潜在应用非常重要，这反过来又将有效地筛选出适用于特定应用的纳米颗粒。
