纳米银/石墨烯SERS基底的制备及石墨烯作用机制

摘要

以乙醇为溶剂、聚乙烯吡咯烷酮为模版剂、以两层石墨烯为平台,采用溶剂热法制备纳米银/石墨烯表面增强拉曼散射(SERS)复合基底,分析石墨烯的作用机制.结果表明:制备的复合基底为70 nm的纳米银多面体附着在表面皱褶的石墨烯上,纳米银多面体为面心立方体;以R6G的1 361 cm-1峰计算,SERS增强因子为1.45×108,拉曼强度ISERS＝5.214lgc+60.67;少层石墨烯的荧光淬灭及自身增强作用,和纳米银粒径增加及高表面能晶面增多,使石墨烯复合基底表现出优异且稳定的表面增强性能.%The surface-enhanced Raman scattering (SERS) substrate of nano-silver particles/graphene was synthesized by sol-vothermal method, in which the ethanol was the solvent, the PVP was used as the template and the two-layer graphene was the platform.And the mechanism of grapheme was analyzed.It is found that the prepared nano silver polyhedron of face-centered cubic with mean grain size of 70 nm is attached to crapy surface of graphene sheets.The SERS enhancement factor reaches to 1.45×108, and ISERS＝5.214lgc+60.67 at 1 361 cm-1of R6G Raman spectra.It is believed that the excellent and stable sur-face-enhanced performance of SERS is caused by the fluorescence quenching of graphene with fewer layers and self enhance-ment, as well as the enlargement of proper size nano silver particles and more lattice planes with higher surface energy.