EPA-97-U1U1-02-101

097

1,820 千元

2008/03/31

2008/12/31

董瑞安

永續發展室(停用)

吳婉怡

國立清華大學生醫工程與環境科學系

環境監測及檢測

核殼奈米複合材料, 分子拓印高分子, 新興污染物, 重金屬, 奈米感測系統, 吸附

Core-shell nanocomposite materials, Molecularly imprinting polymers (MIPs), Emerging pollutants, heavy metals, nanosensing system, adsorption

董瑞安

03-5726785

radoong@mx.nthu.edu.tw

本計畫研究的主要目的在於藉由奈米技術來合成不同材質之核殼複合奈米粒子，並利用表面改質技術將感測元件鍵結於核殼奈米顆粒表面，製作出兼具監測分析與吸附能力的奈米材料，使其能在短時間內即可進行少量與微量樣品的快速分析與吸附微量有機物。研究結果發現共沈澱法可成功用來製備顆粒大小約為8 nm之Fe3O4奈米粒子，而SiO2層厚度可藉由溶膠凝膠參數來調控，當製備條件為 [TEOS] 0.05 M、[NH4OH] 0.15 M及H2O/TEOS比例為180時，為最佳製備Fe3O4/SiO2核殼複合粒子之條件，所得之材料為單一均勻分散且顆粒大小約為120 nm。再藉由自組單分子薄膜技術進行表面修飾，利用THPC配合甲醛還原法，可將金殼層材料均勻附著於二氧化矽核層表面，使所開發的核殼奈米複合材料將具有新穎光學特性，能進行重金屬分析定量。SQUID的結果顯示，所製備的核殼奈米顆粒為超順磁性材料，單獨的 Fe3O4在室溫的飽和磁化量為53.84 emu/g，加入 SiO2及Au殼層後飽和磁化量分別為12.1及2.21 emu/g。經MPA表面修飾之Fe3O4/SiO2/Au對Cu(II)及Cd(II)具有不錯的分析檢測能力，能檢測的最低濃度值約為0.5 ppm，線性範圍則為0.5-100 mg/L；但對Ni(II)的敏感度較低，其線性範圍約僅1個級數(5~100 ppm)。本研究也同時探討應用總體聚合與沈澱聚合製備分子拓印高分子，總體聚合型分子拓印高分子對於-estradiol具有高選擇性及高鍵結能力，最大鍵結量達0.7998 mg/g，而沉澱聚合製備出的分子拓印高分子，可直接製備球狀顆粒，經由簡單地調控官能性單體和交聯劑的比例，即可控制顆粒範圍 (178 – 2472 nm)。此外由SEM、IR、EDX及SQUID的分析結果顯示，所發展的方法是可直接將分子拓印高分子披覆在核殼奈米顆粒上，核殼顆粒仍具有磁性，其在300K的飽和磁化量約為0.34 emu/g。此類材料由於具有表面拓印能力，因此對有機物的吸附在2-5 h間即可達平衡，對acetaminophen及estradiol的吸附量則可達0.243及1.07 mg/g-MIP以上。

核殼奈米複合材料, 分子拓印高分子, 新興污染物, 重金屬, 奈米感測系統, 吸附

total_final.pdf

9MB

[期末報告]公開完整版

2009/3/1 上午 12:00:00

The purpose of this project is to fabricate different types of core-shell nanoparticles for effective detection and adsorption of metal ion as well as emerging pollutants in the environment. The sensing elements were immobilized onto the surface of core-shell nanoparticles by surface modification techniques, and thus can be used for high-throughput and rapid analysis of contaminants in small or trace amounts of samples. TEM and XRPD results show that co-precipitation is a suitable method for fabrication of magnetite (Fe3O4) at around 8 nm. The microstructures and particle sizes of Fe3O4/SiO2 nanoparticles are found to be controlled by several sol-gel parameters. The optimized condition for fabrication of Fe3O4/SiO2 core-shell nanoparticles were: [TEOS], 0.05M, [NH4OH], 0.15M, and H2O/TEOS ratio, 180. In addition, the use of self-assembled monolayer techniques with THPC/formaldehyde reduction methods can successfully coat gold nanoparticles onto the surface of SiO2, which possess novel optical properties for metal ion detection. Results of superconducting quantum interference device (SQUID) showed that the Fe3O4/SiO2/Au core-shell nanoparticles were superparamagnetic nanomaterials. However, the saturation magnetization decreased upon increasing the thickness of shell layer. The value of saturation magnetization for Fe3O4, Fe3O4/SiO2, and Fe3O4/SiO2/Au nanoparticles were 53.84, 12.1 and 2.21 emu/g, respectively. The detection limits for Cu(II) and Cd(II) by MPA-modified Fe3O4/SiO2/Au core-shell nanoparticles was about 0.5 ppm with the dynamic range of 2-3 orders of magnitude. The developed core-shell nanoparticles have less sensitivity toward Ni(II) detection with linear range of 5-100 mg/L. In addition to Fe3O4/SiO2/Au nanoparticles, both bulk polymerization and precipitation polymerization were used to fabricate molecularly imprinting polymers (MIP), which can be detection emerging pollutants. The MIP fabricated with by bulk polymerization method has high selectivity and binding capacity towards -estradiol. The maximum adsorption capacity can be up to 0.799 mg/g. In addition, the particle sizes of MIPs fabricated from precipitation polymerization, ranging from 178 to 2472 nm, which can be easily controlled by changing the ratios of cross linker-to-monomer. Results of SEM, IR, EDS, and SQUID analyses showed that Fe3O4/SiO2/MIP was still a superparamagenetic material. The saturation magnetization at 300 K was 0.34 emu/g, which can be recovered simply by magnetic force. In addition, the equilibrium of organic adsorption by Fe3O4/SiO2/MIP can be achieved within 2-5 h. The adsorbed amounts of acetaminophen and estradiol can be up to 0.243 and 1.07 mg/g-MIP, respectively.

Core-shell nanocomposite materials, Molecularly imprinting polymers (MIPs), Emerging pollutants, heavy metals, nanosensing system, adsorption