Surface-enhanced Raman scattering (SERS) has the theoretical possibility of detecting chemicals at the single molecular level. This potential is frequently limited, however, by the critical requirements of the surface morphology and mechanical stability of SERS substrates. In this paper, we report a new method for fabricating a SERS substrate with a significantly improved mechanical stability and analytical sensitivity, using cellulose nanofibers (CNFs) and gold nanoparticles (AuNPs). We constructed a uniformly CNFs-textured substrate on a glass surface by means of suppressing the “coffee ring” effect of the CNF sessile drop and then introduced an AuNP suspension onto the CNFs-textured substrate by taking advantage of the “coffee ring” effect. A widened detection zone is formed by AuNPs on the CNFs-textured glass, producing a stable SERS substrate for trace analysis and chemical identification. Microscopic and spectroscopic characterizations of the CNF-AuNPs SERS substrate show that the CNFs enhance the stability of both the AuNP clusters and the SERS activity. The CNF-AuNPs SERS substrate is significantly more stable and sensitive than the SERS substrate fabricated by directly depositing the AuNP suspension on a smooth glass surface.

中文翻译：

---

利用“咖啡环”效应对纤维素纳米纤维织造的SERS底物进行痕量分析和化学鉴定

表面增强拉曼散射（SERS）在理论上具有在单个分子水平上检测化学物质的可能性。但是，这种潜力常常受到SERS基材表面形态和机械稳定性的严格要求的限制。在本文中，我们报告了一种使用纤维素纳米纤维（CNF）和金纳米颗粒（AuNPs）制造具有显着改善的机械稳定性和分析灵敏度的SERS基板的新方法。我们通过抑制CNF无柄滴的“咖啡环”效应，在玻璃表面上构造了均匀的CNFs质感基底，然后利用“咖啡环”效应将AuNP悬浮液引入CNFs质感基底上。CNNPs质感玻璃上的AuNPs形成了一个扩大的检测区域，生产出稳定的SERS底物，用于痕量分析和化学鉴定。CNF-AuNPs SERS底物的显微和光谱表征表明，CNF增强了AuNP簇的稳定性和SERS活性。CNF-AuNPs SERS基板比通过直接将AuNP悬浮液沉积在光滑的玻璃表面上制成的SERS基板更加稳定和敏感。