Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS) , UNIST-gil 50, Ulsan 44919, Republic of Korea.
ACS Nano. 2016 Dec 27;10(12):11156-11162. doi: 10.1021/acsnano.6b06153. Epub 2016 Dec 6.
We report on an insulating two-dimensional material, hexagonal boron nitride (h-BN), which can be used as an effective wrapping layer for surface-enhanced Raman spectroscopy (SERS) substrates. This material exhibits outstanding characteristics such as its crystallinity, impermeability, and thermal conductance. Improved SERS sensitivity is confirmed for Au substrates wrapped with h-BN, the mechanism of which is investigated via h-BN thickness-dependent experiments combined with theoretical simulations. The investigations reveal that a stronger electromagnetic field can be generated at the narrowed gap of the h-BN surface, which results in higher Raman sensitivity. Moreover, the h-BN-wrapped Au substrate shows extraordinary stability against photothermal and oxidative damages. We also describe its capability to detect specific chemicals that are difficult to analyze using conventional SERS substrates. We believe that this concept of using an h-BN insulating layer to protect metallic or plasmonic materials will be widely used not only in the field of SERS but also in the broader study of plasmonic and optoelectronic devices.
我们报告了一种绝缘二维材料，六方氮化硼（h-BN），它可用作表面增强拉曼光谱（SERS）衬底的有效包裹层。这种材料具有出色的特性，如结晶度、不渗透性和热导率。通过 h-BN 厚度相关实验和理论模拟的结合，我们证实了用 h-BN 包裹的 Au 衬底的 SERS 灵敏度得到了提高，其机制得到了证实。研究表明，在 h-BN 表面的缩小间隙处可以产生更强的电磁场，从而导致更高的拉曼灵敏度。此外，h-BN 包裹的 Au 衬底对光热和氧化损伤具有非凡的稳定性。我们还描述了它检测特定化学物质的能力，这些化学物质使用传统的 SERS 衬底很难分析。我们相信，使用 h-BN 绝缘层来保护金属或等离子体材料的概念不仅将在 SERS 领域得到广泛应用，而且将在等离子体和光电设备的更广泛研究中得到广泛应用。
