应用γ-射线辐照技术制备纳米厚度片状银粉的研究(英文)

The Preparation of Nano-thickness Flake Silver Powders Using γ-irradiation Technique

在γ-射线辐照下,利用抗坏血酸(Vc)作为还原剂,聚乙烯吡咯烷酮(PVP)作为保护剂,从硝酸银溶液中制备了大量的胶体悬浮态片状银粉。改变辐照剂量、辐照波长、辐照时间、PVP/AgNO3的物质的量之比等反应参数,可以改变所得片状银粉的厚度和大小。球形银粉颗粒(SSP)转化为片状银粉颗粒(FSP)的机理可以用γ-射线诱导分裂与PVP软模板的协同作用解释。通过透射电镜(TEM)和x-射线衍射仪(XRD)对所得片状银粉产物进行了表征。这种γ-射线辐照辅助制备大薄片银粉的方法可以成为工业上传统球磨法的可选替代方法。

A large amount of silver nanoflakes in high yield in form of a colloidal suspension are prepared under γ-irradiation using ascorbic acid (Vc) and polyvinylpyrrolidone (PVP) as a reducing agent and a protect polymer. Changing the experimental parameters such as dose rate of irradiation, irradiation wavelength, time and molar ratio of PVP to AgNO3, the thickness and size of the resulting silver nanoflakes can be adjusted. The conversion process of spherical silver nanoparticles (SSP) to flake-like silver nanoparticles (FSP) can be illustrated by a cooperation mechanism of γ-irradiation induced fragmentation and PVP soft template. The product of FSP is characterized by transmission electron microscopy (TEM) and X-ray powder diffractometer (XRD). This γ-irradiation assisted-preparation method might be a candidate to substitute the traditional ball milling method to obtain thin and large silver flakes in industry.