Department of Chemistry, National University of Singapore , 3 Science Drive 3, 117543, Singapore.
Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore , 6 Science Drive 2, 117546, Singapore.
Nano Lett. 2015 Dec 9;15(12):8331-5. doi: 10.1021/acs.nanolett.5b03966. Epub 2015 Nov 19.
Searching for new plasmonic building blocks which offer tunability and design flexibility beyond noble metals is crucial for advancing the field of plasmonics. Herein, we report that solution-synthesized hexagonal Bi2Te3 nanoplates, in the absence of grating configurations, can exhibit multiple plasmon modes covering the entire visible range, as observed by transmission electron microscopy (TEM)-based electron energy-loss spectroscopy (EELS) and cathodoluminescence (CL) spectroscopy. Moreover, different plasmon modes are observed in the center and edge of the single Bi2Te3 nanoplate and a breathing mode is discovered for the first time in a non-noble metal. Theoretical calculations show that the plasmons observed in the visible range are mainly due to strong spin-orbit coupling induced metallic surface states of Bi2Te3. The versatility of shape- and size-engineered Bi2Te3 nanocrystals suggests exciting possibilities in plasmonics-enabled technology.
寻找新的等离子体构建块，提供超越贵金属的可调性和设计灵活性，对于推进等离子体学领域至关重要。在此，我们报告说，在没有光栅结构的情况下，通过溶液合成的六方 Bi2Te3 纳米板可以表现出覆盖整个可见范围的多种等离子体模式，这可以通过基于透射电子显微镜（TEM）的电子能量损失光谱（EELS）和阴极发光（CL）光谱观察到。此外，在单个 Bi2Te3 纳米板的中心和边缘观察到不同的等离子体模式，并且首次在非贵金属中发现了呼吸模式。理论计算表明，在可见范围内观察到的等离子体主要归因于 Bi2Te3 强自旋轨道耦合诱导的金属表面态。通过形状和尺寸设计的 Bi2Te3 纳米晶体的多功能性为等离子体技术提供了令人兴奋的可能性。
