超细纳米Pd粒子与聚乙烯吡咯烷酮的相互作用

Interaction Between Ultrafine Nano-Pd and Poly(vinylpyrrolidone)

在微量聚乙烯吡咯烷酮(PVP)存在下,利用超声还原氯化钯水溶液,制备出超细纳米Pd颗粒,用高分辨透射电镜、红外光谱、紫外-可见光谱和X射线光电子能谱等技术对其表面形貌及结构进行了表征.结果表明,纳米Pd粒子的粒径均一,大约为3 nm.纳米Pd/PVP复合粉末的羰基红外吸收峰比PVP的羰基吸收峰红移9 cm-1;且当超声反应50 min时,PVP紫外吸收波峰蓝移16 nm,表明了纳米Pd与PVP之间存在一定的相互作用力.XPS结果证明,纳米Pd与PVP的羰基基团通过配位作用使超细纳米Pd粒子得以稳定分散存在.

Ultrafine nano-Pd particles were prepared by ultrasonic without gas protection and reductant in the palladium（Ⅱ） chloride aqueous solution by the addition of a small quantity of poly（vinylpyrrolidone）（PVP）;The samples were characterized by high-resolution transmission electron microscopy（HRTEM）,Fourier transform infrared（FTIR） spectroscopy,ultraviolet-visible（UV-Vis） spectroscopy and X-ray photoelectron spectrum（XPS）.The nano-Pd particles with a uniform size of a diameter of 3 nm were observed by HRTEM.FTIR analysis shows that the characteristic peak of carbonyl in the nano-Pd/PVP composites shifted 9 cm-1 to a lower frequency in comparison with that of the PVP.The results of UV-Vis spectroscopy show that the absorption peak of PVP shifted 16 nm to short wavelength after 50 min ultrasonic.Therefore,there are interactions between Pd and PVP.Based on the proving by XPS,the interactions were formed between the carbonyl group in the composites and the palladium atoms,and were considered to be of coordination and enabled nano-palladium particles to be dispersed stably.