Au@石墨烯量子点复合材料的制备及表面增强拉曼散射应用

Preparation of an Au nanoparticle-graphene oxide quantum dot hybrid and its use in surface-enhanced Raman scattering

以柠檬酸钠为还原剂,采用原位化学还原法制备了Au@石墨烯量子点复合材料。对材料进行了扫描电镜、透射电子显微镜、能谱仪、紫外可见光吸收光谱仪、X射线光电子能谱仪以及拉曼光谱仪等表征。结果表明,复合材料相比于氧化石墨烯量子点的I_G/I_D值增加,说明其石墨化程度有所提高。将复合材料应用到表面增强拉曼散射(SERS)中检测罗丹明6G(R6G),复合基底的SERS强度为Au纳米基底的9倍,是氧化石墨烯量子点基底SERS强度的12倍,表明Au@石墨烯量子点复合材料在SERS检测中具有潜在应用。

An Au nanoparticle-graphene oxide quantum dot hybrid was prepared by the in-situ chemical reduction of HAuCl4 in an aqueous solution containing HAuCl4 and graphene oxide quantum dots using sodium citrate as a reducing agent under reflux for 1 h, followed by repeated centrifugation for three times at 15 000 r/min for 10 min. The hybrid was characterized by SEM, TEM, EDS, UV spectroscopy, XPS and Raman spectroscopy. Results indicated that the IG/ID value of the hybrid was higher than that of graphene oxide quantum dots, indicating that the number of defects was decreased after the reduction. When the hybrid was used in surface enhanced Raman scattering(SERS) to detect rhodamine 6 G, the SERS intensity of the hybrid substrate was 9 times that of a substrate of Au nanoparticles prepared under the same procedure and conditions without adding graphene oxide quantum dots and 12 times that of a graphene oxide quantum dot substrate, indicating that the hybrid has possible use in SERS detection.