化学沉积法制备具有表面增强红外效应的铜纳米粒子

Preparation of Surface Enhanced IR Active Cu Nanoparticles by Wet-Chemical Deposition

利用化学沉积法在锗基底上制备金属铜纳米粒子,探讨了表面活性剂的种类、浓度、沉积时间等因素对铜纳米粒子形貌的影响.以二巯基丁二酸为探针分子,用红外衰减全反射方法(ATR)和红外透射法(TR)考察了所制备的活性基底的红外表面增强效果.用SEM对制备的基底进行了表征.结果显示:(1)1×10-3mol/L的硫酸铜溶液中加入1 mL三乙醇胺表面活性剂,沉积时间为8 h所制备的活性基底在ATR测量时红外增强效果最好,但在红外TR测量时则没有增强信号,其粒径在100 nm左右.(2)1×10-3mol/L的硫酸铜溶液中加入1 mL聚乙二醇400表面活性剂,沉积时间为8 h所制备的活性基底在TR测量时红外增强信号远远大于用ATR测量时的增强信号,其粒径在500 nm左右.该材料在生物样品的检测方面有一定的应用价值.同时考察了所制备的铜纳米粒子的稳定性,结果表明该基底材料具有较好的稳定性.

The copper nanoparticles were prepared on Ge disks by wet-chemical deposition. The influence factors on the morphology of the prepared nanoparticles,such as the type of surfactant,concentration,deposition time,were studied. The surface enhanced infrared absorption（ SEIRA） effect of the Cu nanoparticles were measured in attenuated total reflection spectroscopy（ATR-FTIR）and transmittance spectroscopy（TR-FTIR）using dimercaptosuccinic acid as the probe. The nanostructure of the copper surface was characterized by scanning electron microscopy （ SEM ） . The results show that copper nanoparticles prepared by adding surfactant triethanolamine,a mean particle size of 100 nm,exhibit strong surface enhanced infrared absorption（SEIRA） effect in ATR but no SEIRA in TR. In contrast with this,the as-deposited Cu nanoparticles（500 nm） adding surfactant polyethylene glycol 400 show less SEIRA in ATR and strong SEIRA in TR. These active Cu nanoparticles can be used in biochemistry analysis. The optimized conditions for preparing copper nanoparticles are as follows：（1）1×10^-3 mol/L CuSO4 solution adding 1 mL triethanolamine,depositing on Ge with 8 h for ATR SEIRA material;（2）1×10^-3 mol/L CuSO4 solution adding 1 mL polyethylene glycol 400,depositing on Ge with 8 h for TR SEIRA material. Meanwhile the stability of the copper nanoparticles SEIRA has been studied,it showed that the active Cu nanoparticles have good stability.