毕业论文

打赏
当前位置: 毕业论文 > 化学论文 >

核辐射条件下纳米银合成方法研究+文献综述

时间:2018-03-13 11:20来源:毕业论文
利用还原性多糖(海藻糖)为稳定剂,AgNO3为前驱物,在γ射线的照射下制备纳米银复合材料。在海藻糖硝酸银溶液中,通过γ射线的辐照使水和海藻糖激发产生还原性粒子,将银离子还

摘要纳米银是近年来研究较多的金属纳米材料之一。纳米银由于自身具有小尺寸效应、量子尺寸效应、表面效应和宏观量子隧道效应,因而展现出许多特有性能,如抗菌、催化、导电、导热、三阶非线性光学效应 、表面增强拉曼散射效应等。这些性能使其在医用生物材料、催化、微电子线路、及光电器件等方面存在很好的应用前景。
纳米银的合成有多种途径,包括电离辐射还原、光化学还原、超声辐射法、电化学还原、化学还原、溶胶-凝胶法以及真空蒸镀等。电离辐射还原法是利用辐射生成的还原性粒子H自由基和溶剂化电子(e-aq)将银离子还原成银原子,银原子进一步聚积生成银纳米粒子。与其它方法相比,电离辐射还原具有许多独特的优点:在常温常压下制备,工艺简单,周期短;不需要加入还原剂;产品粒度容易控制, 产率高,制备成本低。而电离辐射还原法又包括激光辐射还原法、辐射水凝胶法等。
本课题利用还原性多糖(海藻糖)为稳定剂,AgNO3为前驱物,在γ射线的照射下制备纳米银复合材料。在海藻糖硝酸银溶液中,通过γ射线的辐照使水和海藻糖激发产生还原性粒子,将银离子还原成银原子,而银原子通过聚集则可以形成纳米粒子。最后再用UV-2401PC型紫外-可见分光光度计测定试样的光吸收性能。19535
关键词:纳米银,电离辐射还原,多糖,γ射线,紫外-可见分光光度计
ABSTRACT
Nano silver is one of the metal nanomaterials research in recent years more.Nano silver because itself has small size effect, quantum size effect, surface effect and   macroscopic quantum tunnel effect, and therefore exhibit many unique properties, such as antibacterial, catalytic, conductive, thermal conductivity, the third order nonlinear optical effects, such as surface enhanced Raman scattering effect.These in the medical biological materials, catalytic performance, microelectronic circuits, and optoelectronic devices, as well as a good application prospect.
The synthesis of silver nanoparticles have a variety of ways, including ionizing radiation reduction, photochemical reduction, ultrasonic radiation method, electrochemical reduction, the sol-gel method, chemical reduction and vacuum deposition, etc. Ionizing radiation reduction method is the use of radiation generated by reducing particle H free radicals and solvation electronic (e - aq) reduction of silver ions into silver atoms, silver atoms further accumulate to silver nanoparticles. Compared with other methods, ionizing radiation reduction has many unique advantages: the preparation under atmospheric pressure, simple technology, short cycle; Don't need to add reducing agent; Product granularity is easy to control, high production rate, low preparation cost. And ionizing radiation reduction method including laser radiation reduction method, radioactive water gel method, etc.
This topic using the reducibility polysaccharide (trehalose) as stabilizer, AgNO3 as precursors, the preparation of silver nanoparticles composites under the irradiation of gamma rays. In trehalose silver nitrate solution by gamma irradiation make water and trehalose reducing particle excitation, the reduction of silver ions in silver atoms, while silver atoms by gathering can form nano particles. Then use UV - 2401 type PC ultraviolet-visible spectrophotometer determination of light absorption performance of the sample.

Key words: nano silver, ionizing radiation reduction, polysaccharide, gamma rays, ultraviolet-visible spectrophotometer
目 录
第一章 绪论    1
1.1 纳米材料简介    1
1.2 纳米银制备方法    1
1.2.1 纳米银的一般制备方法    1
1.2.2 电离辐射还原法制备纳米银材料    2 核辐射条件下纳米银合成方法研究+文献综述:http://www.youerw.com/huaxue/lunwen_10933.html
------分隔线----------------------------
推荐内容