Wang Li, Huang Jian, Su Mei-Juan, Wu Jin-Di, Liu Weisheng
College of Chemistry and Chemical Engineering, Xi'an Shiyou University Xi'an Shaanxi 710065 China
Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 P. R. China
RSC Adv. 2021 Aug 9;11(44):27152-27159. doi: 10.1039/d1ra04874k.
Surface-enhanced Raman scattering (SERS) sensing has always been considered as a kind of high-efficiency analysis technique in different areas. Herein, we report a AgNPs decorated 3D bionic silicon (Si) nanograss SERS substrate with higher sensitivity and specificity by green galvanic displacement. The Si nanograss arrays are directly grown on a Si substrate catalyst-assisted vapor-liquid-solid (VLS) growth and subsequent plasma interaction. AgNPs were rapidly immobilized on Si nanograss arrays without any organic reagents, and avoiding the interference signal of additives. The AgNPs decorated 3D bionic silicon nanograss arrays not only possess a larger specific surface area (loading more reporter molecules), but also provide a potential distribution and arrangement for plentiful hot spots. Using Rhodamine 6G (R6G) as a probe molecule, the prepared SERS substrates exhibited great potential for high-sensitivity SERS sensing, and pushed the limit of detection (LOD) down to 0.1 pM. A higher Raman analytical enhancement factor (AEF, 3.3 × 10) was obtained, which was two magnitudes higher than our previous Ag micro-nano structures. Additionally, the practicality and reliability of our 3D bionic SERS substrates were confirmed by quantitative analysis of the spiked Sudan I in environmental water, with a wide linear range (from 10 M to 10 M) and low detection limit (0.1 nM).
表面增强拉曼散射（SERS）传感一直被认为是不同领域中的一种高效分析技术。在此，我们通过绿色电置换法报道了一种具有更高灵敏度和特异性的AgNPs修饰的三维仿生硅（Si）纳米草SERS基底。硅纳米草阵列通过催化剂辅助的气-液-固（VLS）生长及随后的等离子体相互作用直接生长在硅基底上。无需任何有机试剂，AgNPs就能快速固定在硅纳米草阵列上，避免了添加剂的干扰信号。AgNPs修饰的三维仿生硅纳米草阵列不仅具有更大的比表面积（可负载更多的报告分子），还为丰富的热点提供了电位分布和排列。以罗丹明6G（R6G）作为探针分子，所制备的SERS基底在高灵敏度SERS传感方面展现出巨大潜力，并将检测限（LOD）降低至0.1 pM。获得了更高的拉曼分析增强因子（AEF，3.3×10），比我们之前的Ag微纳结构高出两个数量级。此外，通过对环境水中加标的苏丹红I进行定量分析，证实了我们的三维仿生SERS基底的实用性和可靠性，其线性范围宽（从10⁻⁹ M到10⁻⁶ M）且检测限低（0.1 nM）。
