Department of Life Science, University of Seoul , Seoul 130-743, Republic of Korea.
ACS Nano. 2016 Aug 23;10(8):7639-45. doi: 10.1021/acsnano.6b02903. Epub 2016 Jun 30.
Self-formation of colloidal oil droplets in water or water droplets in oil not only has been regarded as fascinating fundamental science but also has been utilized in an enormous number of applications in everyday life. However, the creation of three-dimensional (3D) architectures by a liquid droplet and an immiscible liquid interface has been less investigated than other applications. Here, we report interfacial energy-driven spontaneous self-formation of a 3D plasmonic optical structure at room temperature without an external force. Based on the densities and interfacial energies of two liquids, we simulated the spontaneous formation of a plasmonic optical structure when a water droplet containing metal ions meets an immiscible liquid polydimethylsiloxane (PDMS) interface. At the interface, the metal ions in the droplet are automatically reduced to form an interfacial plasmonic layer as the liquid PDMS cures. The self-formation of both an optical cavity and integrated plasmonic nanostructure significantly enhances the fluorescence by a magnitude of 1000. Our findings will have a huge impact on the development of various photonic and plasmonic materials as well as metamaterials and devices.
胶体油滴在水中或水滴在油中自形成不仅被视为迷人的基础科学，而且在日常生活中的大量应用中也得到了利用。然而，与其他应用相比，通过液滴和不混溶的液体界面来创建三维（3D）结构的研究还较少。在这里，我们报道了在室温下无需外力驱动，界面能自发形成 3D 等离子体光学结构。基于两种液体的密度和界面能，我们模拟了当含有金属离子的水滴遇到不混溶的液体聚二甲基硅氧烷（PDMS）界面时，等离子体光学结构的自发形成。在界面处，随着液体 PDMS 的固化，液滴中的金属离子被自动还原形成界面等离子体层。光学腔和集成等离子体纳米结构的自形成使荧光显著增强了 1000 倍。我们的发现将对各种光子和等离子体材料以及超材料和器件的发展产生巨大影响。
