Lee So Young, Tsalu Philippe Vuka, Kim Geun Wan, Seo Min Jung, Hong Jong Wook, Ha Ji Won
Department of Chemistry , University of Ulsan , 93 Daehak-Ro , Nam-Gu, Ulsan 44610 , South Korea.
Nano Lett. 2019 Apr 10;19(4):2568-2574. doi: 10.1021/acs.nanolett.9b00338. Epub 2019 Mar 13.
The optimization of the localized surface plasmon resonance (LSPR)-decaying channels of hot-electrons is essential for efficient optical and photochemical processes. Understanding and having the ability to control chemical interface damping (CID) channel contributions will bring about new possibilities for tuning the efficiency of plasmonic hot-electron energy transfer in artificial devices. In this scanning electron microscopy-correlated dark-field scattering study, the CID was controlled by focusing on the electronic nature of disubstituted benzene rings acting as adsorbates, as well as the effects of sharp tips on gold bipyramids (AuBPs) with similar aspect ratios to those of gold nanorods. The results showed that the sharp tips on single AuBPs, as well as the electronic effects of the adsorbate molecules, increase the interfacial contact between the nanoparticles and adsorbate molecules. Electron withdrawing groups (EWGs) on the adsorbates induce larger homogeneous LSPR line widths compared to those of electron donating groups (EDGs). Depending on the location (ortho, meta, and para) of the EDG, the effect of benzene rings with an EDG, which was considered to be induced by sulfur atoms bound to the nanoparticle surface, is weakened by the back transfer of electrons facilitated by the difference in the availability of the electrons of the EDG. Therefore, this study reports that the CID in the LSPR total decay channels can be tuned by controlling the electron withdrawing and electron donating features of adsorbate molecules with the surface topology of metal.
优化热电子的局域表面等离子体共振（LSPR）衰减通道对于高效的光学和光化学过程至关重要。理解并能够控制化学界面阻尼（CID）通道的贡献将为调节人工器件中等离激元热电子能量转移的效率带来新的可能性。在这项与扫描电子显微镜相关的暗场散射研究中，通过关注作为吸附质的二取代苯环的电子性质以及具有与金纳米棒相似纵横比的金双锥体（AuBP）上尖锐尖端的影响来控制CID。结果表明，单个AuBP上的尖锐尖端以及吸附质分子的电子效应增加了纳米颗粒与吸附质分子之间的界面接触。与供电子基团（EDG）相比，吸附质上的吸电子基团（EWG）会导致更大的均匀LSPR线宽。取决于EDG的位置（邻位、间位和对位），被认为是由与纳米颗粒表面结合的硫原子诱导的带有EDG的苯环的效应，会因EDG电子可用性差异促进的电子回传而减弱。因此，本研究报告称，通过利用金属的表面拓扑结构控制吸附质分子的吸电子和供电子特性，可以调节LSPR总衰减通道中的CID。
