液相脉冲激光烧蚀法制备高熔点的纳米金属粒子

Laser Ablated Preparation of Noble Metal Nanoparticles in Liquid

采用液相脉冲激光烧蚀法成功地制备了高熔点的金属Pt、Ru与Ag纳米粒子.采用SEM、TEM、ED和紫外-可见吸收光谱表征了纳米粒子的特征.纳米粒子的粒径基本在数个到数十个纳米的大小范围内.发现含适量PVP(poly(vinylpyrrolidone))的水溶液有利于纳米粒子的制备,而且还能够提高纳米粒子悬浮液的稳定性.该制备方法较简单,在制备高熔点的纳米金属粒子方面有着其它方法所不能比拟的优势.

Nanoparticles were synthesized under pulsed laser ablation of Pt, Ru, and Ag in water with or without PVP（poly（vinylpyrrolidone）. Scanning electron microscopy, high resolution transmission electron microscopy, selected area electron diffraction and UV-Vis absorption spectroscopy were used to characterize the nanoparticles. Nano-sized particles were found to be in the range from several to tens nanometers. The plasma absorption bands of generated Pt, Ru, and Ag nanoparticles at around 254, 300, and 420 nm were observed. The water solution containing PVP with appropriate concentration was found to be in favor of the formation of noble metal nanoparticles and to be capable of stabilizing nanoparticle suspensions. Meanwhile, the mechanism of the formation of nanoparticles by laser ablation in liquid media was discussed. Results suggested that the colloidal solution of noble metal nanoparticles could be obtained simply by pulsed laser ablation of their bulk as targets in liquid, indicating the advantage over other methods especially for the synthesis of noble metals with high melting points.