可调谐金纳米棒近红外光谱特性及表面增强拉曼特性

Near Infrared SERS Properties of Tunable Gold Nanorods

采用种子生长法制备金纳米棒,通过改变制备过程中硝酸银、金种子以及盐酸溶液的配比,制备得到了4种不同长径比的金纳米棒颗粒样品,用透射电子显微镜测定了样品形貌,还测定了样品的近红外吸收光谱及拉曼增强特性。结果表明,随着金纳米棒长径比的增大,纵向吸收峰会发生红移,而横向吸收峰几乎不变。在波长为785nm的激光照射下,以金纳米棒作为表面拉曼增强基底,罗丹明6G分子的拉曼信号得到了显著增强。

In this paper, gold nanorods are fabricated by using seed-mediated growth method . Four kinds of gold nanorods particle samples with different length-diameter ratios are prepared through changing proportion among AgNO 3, Au seeds, and HCl solution. The morphology of the samples are measured by transmission electron microscope (TEM), and the near infrared absorption spectra and Raman enhancement characteristics of the samples are also measured. The results show that with the increase of the length-diameter ratio gold nanorods, the longitudinal surface plasmon resonance (LSPR) absorption peak shifts red while the transverse surface plasmon resonance (TSPR) absorption peak almost remains unchanged. By using the gold nanorods as the surface-enhanced Raman substrate, Raman signal of Rhodamine 6 G molecule irradiated by 785 nm laser is significantly enhanced. These results provide a reference and a basis for the application of gold nanorods in the fields of bio-molecular recognition and detection in the near infrared spectrum.