Wang Y W, Hong Byung Hee, Kim Kwang S
National Creative Research Initiative Center for Superfunctional Materials, Department of Chemistry, Division of Molecular and Life Sciences, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea.
J Phys Chem B. 2005 Apr 21;109(15):7067-72. doi: 10.1021/jp046423v.
We introduced a simple chemical method to synthesize semimetal bismuth nanoparticles in N,N-dimethylformamide (DMF) by reducing Bi(3+) with sodium borohydride (NaBH(4)) in the presence of poly(vinylpyrroldone) (PVP) at room temperature. The size and dispersibility of Bi nanoparticles can be easily controlled by changing the synthetic conditions such as the molar ratio of PVP to BiCl(3) and the concentration of BiCl(3). The UV-visible absorption spectra of Bi nanoparticles of different diameters are systematically studied. The surface plasmon peaks broaden with the increasing molar ratio of PVP to BiCl(3) as the size of bismuth nanoparticles decreases. Infrared (IR) spectra of the complexes with different molar ratios of PVP/BiCl(3) show a strong interaction between the carboxyl oxygen (C=O) of PVP and Bi(3+) ion and a weak interaction between the carboxyl oxygen (C=O) of PVP and the Bi atom in nanoparticles. This indicates that PVP serves as an effective capping ligand, which prevents the nanoparticles from aggregation.
我们介绍了一种简单的化学方法，在室温下于N，N-二甲基甲酰胺（DMF）中，通过在聚乙烯吡咯烷酮（PVP）存在下用硼氢化钠（NaBH₄）还原Bi(3+)来合成半金属铋纳米颗粒。通过改变合成条件，如PVP与BiCl₃的摩尔比以及BiCl₃的浓度，可以轻松控制铋纳米颗粒的尺寸和分散性。系统研究了不同直径的铋纳米颗粒的紫外可见吸收光谱。随着铋纳米颗粒尺寸减小，表面等离子体峰随着PVP与BiCl₃摩尔比的增加而变宽。不同摩尔比PVP/BiCl₃的配合物的红外（IR）光谱表明，PVP的羧基氧（C=O）与Bi(3+)离子之间存在强相互作用，而PVP的羧基氧（C=O）与纳米颗粒中的铋原子之间存在弱相互作用。这表明PVP作为一种有效的封端配体，可防止纳米颗粒聚集。
