文档介绍：青岛科技大学
本科毕业设计(论文)
金纳米颗粒的制备及其表面包覆
题目__________________________________
__________________________________
指导教师__________________________
辅导教师__________________________
0904020212
学生姓名__________________________
学生学号__________________________
092
材料科学与工程学院
材料化学
_______________________________院(部)____________________________专业________________班
6
2013
17
______年___月___日
金胶体的制备与包覆
摘要
金溶胶也称胶体金。是一种以稳定形式存在于溶液中的金颗粒,根据粒径大小不同,其颜色呈桔红色到紫红色变化。具有由强烈的光学吸收和光学散射所构成的等离子体共振性能。此外,还具有独特的光学、电学、磁学、催化效应和特殊的生物亲和效应。这些特殊的性质,使其在生物传感器、光电子器件、催化,生物医药,免疫诊断等领域具有广泛的应用前景。但是其不稳定,易团聚,而作为核壳结构的Au/SiO2可以改善以上诸多缺点,大大改善其稳定性,提高胶体分散性,避免团聚,另外,二氧化硅是一种惰性材料,易进行表面功能化,赋予金溶胶更广泛的应用前景。
本文中,采用湿化学还原法,通过控制还原剂(柠檬酸钠)的用量,制备不同尺寸的金胶体,研究了还原剂对胶体纳米粒子尺寸的影响效果。然后通过溶胶-凝胶技术,利用正硅酸乙脂为硅源包覆金胶体,在控制变量的情况下,研究制备了不同粒径的金纳米颗粒的包覆及二氧化硅壳层厚度控制。
关键词: 金胶体; Au/SiO2;还原法;溶胶凝胶。
PREPARATION OF COLLOIDAL GOLD AND Au/SiO2
ABSTRACT
Gold colloids, is stable gold particles present in solution. Its color varies from orange red to purple according to different size. It has the property of plasmon resonance due to strong optical absorption and scattering. Moreover, it has unique optical, electrical, ic, catalytic properties and special biological affinity effect. These special properties make it has wide application in biosensors, optoelectronic devices, catalysis, bio-medicine, immune-diagnostic and other fields. However, it is unstable, trends to aggregate. Au/SiO2 core-shell structure can improve this ing. It greatly improves stability, colloidal dispersion and prevents agglomeration. In addition, the silica is an inert material and easy for surface functionalization, giving more applications to colloidal gold.
In this paper, we prepare various sizes of gold nanoparticles by wet chemical reduction method, the size was controlled by the reducing agent (sodium citrate) of dosage. In this way, we research the relationship of dosage of reducing agent and nanoparticles of size. Then, sol-gel technique was adopted to produce silica shel