Yang Fan, Ye Shunsheng, Dong Wenhao, Zheng Di, Xia Yifan, Yi Chenglin, Tao Jing, Sun Chang, Zhang Lei, Wang Lu, Chen QianYun, Wang Yazi, Nie Zhihong
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, China.
Key Laboratory for Organic Electronics and Information Displays & Institute of Advanced Materials, Nanjing University of Posts & Telecommunications, Nanjing, 210023, China.
Adv Mater. 2021 Jun;33(24):e2100325. doi: 10.1002/adma.202100325. Epub 2021 May 10.
The application of plasmonic dimeric nanostructures in color displays, data storage, and especially metamaterials necessitates the patterning of dimers into ordered arrays, but controllable assembly of plasmonic nanoparticles into patterned dimer arrays on substrates still remains a challenge. Here, a facile laser-scanning-based strategy to fabricate quasi-3D patterned arrays of plasmonic nanoparticle dimers with controlled orientation for plasmonic information encryption is reported. Laser scanning of polymer-covered plasmonic nanoparticle (e.g., gold) arrays selectively exposes the surface of irradiated nanoparticle via localized photothermal heating, guiding the assembly of another type of nanoparticles onto the exposure nanoparticle surface to form dimers on substrates. This combined top-down/bottom-up approach is highly flexible in forming high-resolution patterns of plasmonic dimers from nanoparticles of different sizes and shapes. The z-axis orientation, interparticle spacing, and nanoparticle size and shape of plasmonic dimers can be precisely tuned, enabling the modulation of the coupled resonances of the dimer arrays. Moreover, it is demonstrated that the patterned dimer arrays can be used in information encryption where their plasmonic color can be repeatedly displayed and erased. This work provides an important addition to tools for the fabrication of patterned complex plasmonic nanostructures from as-synthesized nanoparticles with broad applications.
等离子体二聚体纳米结构在彩色显示、数据存储，尤其是超材料中的应用需要将二聚体图案化为有序阵列，但将等离子体纳米颗粒可控地组装成基底上的图案化二聚体阵列仍然是一个挑战。在此，报道了一种基于激光扫描的简便策略，用于制造具有可控取向的等离子体纳米颗粒二聚体的准三维图案化阵列，以进行等离子体信息加密。对聚合物覆盖的等离子体纳米颗粒（如金）阵列进行激光扫描，通过局部光热加热选择性地暴露被照射纳米颗粒的表面，引导另一种类型的纳米颗粒组装到暴露的纳米颗粒表面上，从而在基底上形成二聚体。这种自上而下/自下而上相结合的方法在由不同尺寸和形状的纳米颗粒形成等离子体二聚体的高分辨率图案方面具有高度的灵活性。等离子体二聚体的z轴取向、颗粒间间距以及纳米颗粒的尺寸和形状都可以精确调节，从而实现对二聚体阵列耦合共振的调制。此外，还证明了图案化二聚体阵列可用于信息加密，其中它们的等离子体颜色可以反复显示和擦除。这项工作为从合成的纳米颗粒制造具有广泛应用的图案化复杂等离子体纳米结构的工具增添了重要内容。
