茶多酚纳米银的制备及其对直接蓝15的催化降解性能

Synthesis of silver nanoparticles with tea polyphenols and catalytic performance for reductive degradation of Direct Blue 15

利用茶多酚作为还原剂和稳定剂来制备纳米银,所得茶多酚纳米银溶液在紫外-可见吸收光谱430 nm处存在明显的吸收峰,经激光粒径仪分析所得茶多酚纳米银粒子的平均直径为68.42 nm。为了探究茶多酚纳米银粒子的催化性能,文章使用茶多酚纳米银和还原剂硼氢化钠对直接蓝15进行催化降解,经过80 min的反应后,直接蓝15的降解率在添加纳米银的条件下达到91%;而如果溶液中不添加纳米银粒子,相同时间后直接蓝15的降解率只有35%。经过还原降解后,直接蓝15大分子结构中的偶氮基发生断裂,从而破坏了染料的发色体系。

The tea polyphenols silver nanoparticles prepared with tea polyphenols as reducing and capping agent shows an obvious absorption peak at 430 nm in the UV-vis absorption spectrum. The average diameter of Ag NPs in the solution was detected to be around 68. 42 nm with optical particle size analyzer. In order to study the catalytic performance of Ag NPs,catalytic degradation of Direct Blue 15 was performed by using Ag NPs and Na BH4（ reducing agent）,and it was found that the degradation rate of Direct Blue 15 reached up to 91% after 80 min reaction if silver nanoparticles were added,while the degradation rate was only 35% if no silver nanoparticle was added under the same conditions. The azo groups in the macromolecular structure of Direct Blue 15 were broken after reductive degradation,which destroyed the chromophoric system of dye.