金奈米粒子之合成及鑑定－統整型化學實驗實例

Synthesis and Characterizations of Gold Nanoparticles-An Integrated Undergraduate Chemical Experiment

佘瑞琳(Jui-Lin She) ； 張英德(Ying-Der Chang) ； 張煥宗(Huan-Tsung Chang) ； 陳竹亭(Jwu-Ting Chen)

《化學》 62卷4期 (2004/12) Pp. 563-568

https://doi.org/10.6623/chem.2004047

摘要

本研究之目的在設計適合大學基礎化學之統整型實驗教材。應用一般大二有機化學實驗室之基本設備，操作四氯金酸（HAuCl_4）經檸檬酸鈉（C_6H_5O_7Na_3）還原反應，合成尖端科技奈米級材料－金奈米粒子。由金奈米粒子懸浮溶液之外觀顏色及可見光吸收光譜，印證奈米級材料之特性，建立一個由合成至物性鑑定的統整型材料化學實驗。金奈米粒子之製備乃使用學生實驗室之迴流加熱裝置，利用檸檬酸鈉與四氯金酸相對用量之差異調控金奈米粒子粒徑，獲得粒徑約為15 或33 nm 之金奈米粒子，其溶液分別呈酒紅及紫紅色，用紫外光/可見光光譜儀測定其表面電漿共振最大吸收波長分別為520 及528 nm。此實驗經試做確認實驗條件後，編纂成實驗教材，由30 位大二暑修學生二人一組進行試作實驗。其中8 組學生，以3.5 mL、38.8 mM 檸檬酸鈉溶液與30 mL、1 mM 四氯金酸溶液反應，製得金奈米粒子溶液之表面電漿共振最大吸收波長範圍為519~522 nm，平均為521 nm；餘7 組學生以1.5 mL、38.8 mM 檸檬酸鈉溶液反應，製得金奈米粒子溶液之表面電漿共振最大吸收波長範圍為525~531 nm，平均為529 nm。結果顯示，檸檬酸鈉用量多者，所得之金奈米粒子呈對稱球形、粒徑小且粒徑分布窄，製備條件較易控制。反之，檸檬酸鈉用量少，反應所得金奈米粒子形狀較不對稱、粒徑大且粒徑分布廣。學生自此統整型材料化學實驗過程可學習奈米級材料之製備及光譜分析鑑定；同時學習基本合成反應操作、吸量管使用、迴流加熱、分光光譜儀操作等實驗技能。

關鍵字

金奈米粒子 ； 材料化學 ； 統整型大學化學實驗

並列摘要

An integrated 4 work-hour undergraduate chemical experiment in the synthesis and characterizations of gold nanoparticles has been developed. The operation of nano-scale materials is included in the fundamental Chem Lab IV to enhance the interest of chemistry major students. Gold nanoparticles with the diameters of 15 and 33 nm were prepared by using 3.5 and 1.5 mL of 38.8 mM sodium citrate, respectively, to reduce a 30 mL of 1 mM HAuCl_4 solution. UV-Visible spectra for the solutions of the gold nanoparticles were measured, and the characteristic λ_(max) were obtained at 520 and 528 nm, respectively. With such reaction conditions, a new experiment for Chem Lab IV is constructed and added to the chem-major lab manual of NTU. The pilot study has been carried out by 30 students of 2003 summer school at NTU. Most students (70%) had the synthesis of the gold nanoparticles successful. The measured λ_(max) of plasma absorption were ranged from 519~522 and 525~531 nm with the averages at 521 and 529 nm for the two sizes of gold nanoparticles, respectively. In this experiment, basic skills and apparatus for organic chemistry lab, i.e. round-bottom flask, condenser, sand (or oil) bath, and hotplate will be needed extensively. Other lab skills, such as cleaning the glassware using aqua regia, constructing reflux system, and analyzing the UV-Vis spectra are practiced in this experiment. The need for the amount of HAuCl_4 has been minimized so that the cost and chemical waste are reduced.

並列關鍵字

gold nanoparticles ； materials chemistry ； integrated undergraduate laboratory