Lin Shuang, Guan Haoyu, Liu Yuqi, Huang Shinian, Li Junming, Hasi Wuliji, Xu Yizhuo, Zou Jixin, Dong Bin
Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, Key Laboratory of Photosensitive Materials&Devices of Liaoning Province, School of Physics and Materials Engineering, Dalian Minzu University, Dalian 116600, China.
National Key Laboratory of Science and Technology on Tunable Laser, Harbin Institute of Technology, Harbin 150080, China.
ACS Appl Mater Interfaces. 2021 Nov 10;13(44):53289-53299. doi: 10.1021/acsami.1c18565. Epub 2021 Oct 27.
Tuning and controlling the plasmon coupling of noble metal nanoparticles are significant for enhancing their near-field and far-field responses. In this work, a novel heterogeneous plasmonic assembly with a controllable hot spot model was proposed by the conjugation of Au nanospheres (NSs) and Au@Ag core-shell nanocube (NC) films. Three hotspot configurations including point-to-point type, point-to-facet type, and facet-to-facet type were fabricated and transformed simply by adjusting the doping ratio of nanoparticles in the co-assembly film. Expectedly, the localized surface plasmon resonance (LSPR) property and surface-enhanced Raman scattering (SERS) performance of the binary assembly film exhibit distinct diversity due to the change in the hotspot conformation. Interestingly, the point-to-facet hotspot in hybrid assembly films can provide the most extraordinary enhancement for SERS behavior compared with single-component Au NS and Au@Ag NC plasmonic assemblies, which is further confirmed by the finite-different time-domain simulation results of dimer nanostructures. In addition, the two-dimensional binary assemblies of Au NS doping in Au@Ag NCs with excellent sensitivity and high reproducibility were successfully applied in the identification of ketamine. This work opens a new avenue toward the fabrication of plasmonic metal materials with collective LSPR properties and sensitive SERS behavior.
调节和控制贵金属纳米颗粒的等离子体耦合对于增强其近场和远场响应具有重要意义。在这项工作中，通过金纳米球（NSs）与金@银核壳纳米立方体（NC）薄膜的共轭，提出了一种具有可控热点模型的新型异质等离子体组装体。通过简单地调节共组装薄膜中纳米颗粒的掺杂比例，制备并转变了包括点对点型、点对面型和面对面型在内的三种热点构型。不出所料，由于热点构象的变化，二元组装薄膜的局域表面等离子体共振（LSPR）特性和表面增强拉曼散射（SERS）性能表现出明显的差异。有趣的是，与单组分金纳米球和金@银纳米立方体等离子体组装体相比，混合组装薄膜中的点对面热点对SERS行为具有最显著的增强作用，二聚体纳米结构的时域有限差分模拟结果进一步证实了这一点。此外，具有优异灵敏度和高重现性的金纳米球掺杂在金@银纳米立方体中的二维二元组装体成功应用于氯胺酮的识别。这项工作为制备具有集体LSPR特性和灵敏SERS行为的等离子体金属材料开辟了一条新途径。
