García-Lojo Daniel, Rodal-Cedeira Sergio, Núñez-Sánchez Sara, Arenas-Esteban Daniel, Polavarapu Lakshminarayana, Bals Sara, Pérez-Juste Jorge, Pastoriza-Santos Isabel
CINBIO, Universidade de Vigo, Departamento de Química Física, Campus Universitario As Lagoas, Marcosende, 36310 Vigo, Spain.
Galicia Sur Health Research Institute (IIS Galicia Sur), 36310 Vigo, Spain.
Chem Mater. 2024 Sep 13;36(18):8763-8772. doi: 10.1021/acs.chemmater.4c01443. eCollection 2024 Sep 24.
Noble metal nanoparticles, particularly gold and silver nanoparticles, have garnered significant attention due to their ability to manipulate light at the nanoscale through their localized surface plasmon resonance (LSPR). While their LSPRs below 1100 nm were extensively exploited in a wide range of applications, their potential in the near-infrared (NIR) region, crucial for optical communication and sensing, remains relatively underexplored. One primary reason is likely the limited strategies available to obtain highly stable plasmonic nanoparticles with tailored optical properties in the NIR region. Herein, we synthesized AuAg nanorattles (NRTs) with tailored and narrow plasmonic responses ranging from 1000 to 3000 nm. Additionally, we performed comprehensive characterization, employing advanced electron microscopy and various spectroscopic techniques, coupled with finite difference time domain (FDTD) simulations, to elucidate their optical properties. Notably, we unveiled the main external and internal LSPR modes by combining electron energy-loss spectroscopy (EELS) with surface-enhanced Raman scattering (SERS). Furthermore, we demonstrated through surface-enhanced infrared absorption spectroscopy (SEIRA) that the NRTs can significantly enhance the infrared signals of a model molecule. This study not only reports the synthesis of plasmonic NRTs with tunable LSPRs over the entire NIR range but also demonstrates their potential for NIR sensing and optical communication.
贵金属纳米颗粒，特别是金和银纳米颗粒，因其能够通过局域表面等离子体共振（LSPR）在纳米尺度上操纵光而备受关注。虽然它们在1100 nm以下的LSPR在广泛的应用中得到了广泛利用，但其在近红外（NIR）区域（对光通信和传感至关重要）的潜力仍相对未得到充分探索。一个主要原因可能是在近红外区域获得具有定制光学特性的高度稳定的等离子体纳米颗粒的可用策略有限。在此，我们合成了具有1000至3000 nm范围内定制且窄的等离子体响应的金银纳米摇铃（NRTs）。此外，我们进行了全面表征，采用先进的电子显微镜和各种光谱技术，并结合有限时域差分（FDTD）模拟，以阐明它们的光学特性。值得注意的是，我们通过将电子能量损失谱（EELS）与表面增强拉曼散射（SERS）相结合，揭示了主要的外部和内部LSPR模式。此外，我们通过表面增强红外吸收光谱（SEIRA）证明，NRTs可以显著增强模型分子的红外信号。这项研究不仅报道了在整个近红外范围内具有可调LSPR的等离子体NRTs的合成，还展示了它们在近红外传感和光通信方面的潜力。
