基于自组装纳米粒子的三脚状结构阵列作为表面增强拉曼散射基底。

Self-assembly nanoparticle based tripetaloid structure arrays as surface-enhanced Raman scattering substrates.

机构信息

National Key Laboratory of Science and Technology on Micro/Nano Fabrication, Institute of Microelectronics, Peking University, Beijing 100871, People’s Republic of China.

出版信息

Nanotechnology. 2012 Sep 28;23(38):385303. doi: 10.1088/0957-4484/23/38/385303. Epub 2012 Sep 4.

DOI:10.1088/0957-4484/23/38/385303

PMID:22948251

Abstract

This paper reports a novel highly ordered tripetaloid structure array (TPSA) which performs very well as an active surface-enhanced Raman scattering (SERS) substrate. The TPSA is easily fabricated by anisotropic etching of a self-assembly silica-nanoparticle bilayer and a subsequent metal deposition step, with notable uniformity and reproducibility. Electromagnetic simulation indicates that the narrow inter-gaps and edge protrusions in the TPSA act as hot spots. In addition, the peak electromagnetic field intensity in the inter-gaps changes slightly and periodically as the polarization of the incident light varies from 0° to 360°. SERS experiments show that the SERS enhancement factor (EF) of a Au-film-covered TPSA is 12 times higher than that of regular Au-film-over-nanoparticles, and not sensitive to the polarization of the incident light. The spatially averaged EF of the TPSA is as high as 5.7 × 10(6), and the local EF of its hot spots is much higher.

摘要

本文报道了一种新型的高度有序的三叶状结构阵列（TPSA），它作为一种活性表面增强拉曼散射（SERS）基底表现得非常出色。TPSA 是通过各向异性刻蚀自组装二氧化硅纳米粒子双层和随后的金属沉积步骤来轻松制造的，具有显著的均匀性和可重复性。电磁模拟表明，TPSA 中的窄间隙和边缘突出部分充当热点。此外，随着入射光的偏振从 0°到 360°变化，间隙中的峰值电磁场强度会发生轻微且周期性的变化。SERS 实验表明，Au 薄膜覆盖的 TPSA 的 SERS 增强因子（EF）比常规的 Au 薄膜覆盖纳米粒子高 12 倍，并且对入射光的偏振不敏感。TPSA 的空间平均 EF 高达 5.7×10(6)，其热点的局部 EF 更高。