二羧酸鏈長對環保碳奈米點光致發光之影響

本論文探討螢光碳奈米點(簡稱碳點)的碳源，其碳鏈長度與量子產率(QY)的關聯性。使用環保與簡便之水熱法製備一系列具有高量子產率的碳點。以五種不同碳鏈長度之二羧酸作為碳源，並加入不同比例之表面鈍化劑(乙二胺)與螯合劑(氫氧化鎂)來提升碳點量子產率，研究最適合提升量子產率的合成比例並確認量子產率與碳源碳鏈長度之間的關聯性，量子產率最高達到31.50%。以綠色化學的角度合成碳點，溶劑為二次水，所合成出的碳點水溶性極佳，只需經0.22 μm濾頭過濾不需額外處理即具有高量子產率。該碳點之水溶液在可見光下為淡黃色，在紫外光照射下則發出藍色螢光。實驗所合成之碳點，皆使用紫外線-可見光光譜儀測量其最大吸收波長、螢光光譜儀測量其光致發光的性質與傅立葉紅外線光譜儀鑑定其化學官能基。所有碳點在室溫下儲存近六個月，仍保持良好螢光強度，顯示具有廣大的運用潛力。更進一步，此研究所合成的碳點能做為藥物載體或生物成像的標的物。

關鍵字

水熱法；碳奈米點；量子產率；光致發光

並列摘要

This research is to investigate the relation between the length of carbon chain as carbon source and quantum yield (QY), and how to obtain the maximum QY using a green and simple method - hydrothermal synthesis, to produce series of fluorescent carbon dots (CDs). To carry out the experiment, five variations of dicarboxylic acids with different length of carbon chain as carbon source are used. They are then doped with different proportions of ethylenediamine(EDA) which acts as a representative surface passivation agent, and with magnesium hydroxide (Mg(OH)2) as a representative chelation agent to enhance the QY. After the research, the most suitable synthesis proportion to enhance the QY is discovered, and the relation between QY and length of carbon chain as carbon source is also understood. As a result, highest value of QY (31.50%) was achieved. In green chemistry, the solvent used in reactions to synthesize CDs was ultrapure water which makes the CDs totally soluble in water. More than that, CDs need only to be filtered by 0.22 μm filter and no any additional treatment will be needed. The aqueous solution of the CDs was light yellow when observed under visible light and emitted blue fluorescence if irradiated by ultraviolet light. All the CDs in experiments were measured by the UV-Vis spectrometer for their absorbance, fluorescence spectrometer was used to record their properties of photoluminescence and FTIR was used to appraise the chemical functional groups. All the samples are stored at room temperature for almost six months and they still retain their fluorescence intensity. The long duration of fluorescence intensity shows its potential for broad application. Furthermore, we used carbon dots and 5-fluorouracil (5-FU) under ultrasonic oscillation. The CDs produced in this research could be used as a drug carrier or bio-imaging marker.

並列關鍵字

hydrothermal ； carbon nanodots ； quantum yield ； plotoluminescence

參考文獻

1. Derfus AM, Chan WCW, Bhatia SN. Probing the cytotoxicity of semiconductor quantum dots. Nano Lett 2004;4:11-8.

2. Sahoo R, Roy A, Ray C, Mondal C, Negishi Y, Yusuf SM, et al. Decoration of Fe3O4 base material with Pd loaded CdS nanoparticle for superior photocatalytic efficiency. J Phys Chem C 2014;118:11485-94.

3. Mewada A, Pandey S, Shinde S, Mishra N, Oza G, Thakur M, et al. Green synthesis of biocompatible carbon dots using aqueous extract of Trapa bispinosa peel. Mater Sci Engineering C, 2013;33:2914-7.

4. Baker SN, Baker AG. Luminescent carbon nanodots: emergent nanolights. Angew Chem Int Ed 2010;49:6726-44.

5. Shen J, Zhu Y, Yang X, Li C. Graphene quantum dots: emergent nanolights for bioimaging, sensors, catalysis and photovoltaic devices. Chem Commun 2012;48:3686-99.

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二羧酸鏈長對環保碳奈米點光致發光之影響

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