阴离子表面活性剂作为添加剂种子生长法制备尺寸可调的单分散金纳米棒

以不同阴离子表面活性剂作为添加剂种子生长法制备金纳米棒,并考察阴离子表面活性剂种类对金纳米棒形貌及光学性质的影响。在十二烷基苯基磺酸钠(SDBS)存在下,金纳米棒的产率明显高于使用十二烷基磺酸钠的反应体系。对添加SDBS的种子生长法制备金纳米棒的反应条件进行优化,得到十六烷基三甲基溴化铵、SDBS、抗坏血酸和硝酸银的最佳浓度分别为0.04 mol.L-1、2.4 mmol.L-1、1.2 mmol.L-1和0.08 mmol.L-1。在此条件下,金纳米棒的生长在30 min内完成,所制备的金纳米棒表面等离子共振吸收峰位于823 nm,其横纵比为(5±0.03)。当改变生长液中硝酸银浓度时,金纳米棒的尺寸也随之发生改变。此外,我们还探讨了SDBS的作用机理。相对于经典种子生长法,新方法制备纳米金棒在尺寸可调性、单分散性和生物毒性方面明显改善,可广泛应用于各种光学及生物分析。

Seed-Mediated Synthesis of Size-Tunable and Monodisperse Gold Nanorods through the Use of Anionic Surfactant as Additives

Different anionic surfactant was empolyed as additive for the seed-mediated synthesis of gold nanorods and effect of the kind of anionic surfactant on the morphology and optical property of gold nanorods were also investigated. In the presence of sodium dodecyl benzene sulfonate (SDBS), the yield of gold nanorods is obviously higher that of the reaction system using sodium dodecyl sulfate. The reaction conditions of the seed-mediated synthesis of gold nanorods added SDBS were optimized, and the optimal concentrations of hexadecyltrimethylammonium bromide, SDBS, ascorbic acid and silver nitrate were found to be 0.04 mol·L^-1, 2.4 mmol·L^-1, 1.2 mmol·L^-1 and 0.08 mmol·L^-1, respectively. Under the condition, the growth of gold nanorods can complete within 30 minutes, the as-prepared gold nanorods offer a surface plasmon resonance absorption with a maximum absorption peak at 823 nm and aspect ratio of (5±0.03). When changing silver nitrate concentration in the growth solution, the size of gold nanorods also changed. In addition, we also discussed the action mechanism of SDBS. In comparsion with classical seed-mediated synthesis method, proposed method for synthesis of gold nanorods shows an obvious improvement of size adjustable, monodispersity and biological toxicity, and it can be widely applied to a variety of optical and biological analysis.