具多重形狀奈米材料之合成與特性分析

Synthesis and Characterization of Multi-shaped Nano-materials

陳浩銘(Hao Ming Chen)

指導教授 ： 劉如熹

國立臺灣大學/理學院/化學研究所/博士(2008年)

https://doi.org/10.6342/NTU.2008.02372

摘要

本研究著重於零維(0-D)與一維(1-D)奈米材料之合成，零維材料部分包含以金屬原子與離子之氧化還原取代反應製備具中空結構之金屬奈米粒子，由實驗參數之調控進一步控制金屬球殼元素組成；以化學蝕刻將球殼粒子轉化成具多孔性奈米孔道結構之粒子，此新穎結構較商用觸媒具較高催化活性；以還原劑強弱之控制誘導金屬非等向性成長，進一步控制金屬奈米粒子之形貌並探討其成長機制；成功製備均勻之四氧化三鈷奈米方塊，並以還原法將原不具磁性之奈米方塊轉變為僅表面具磁性，使其可自組裝形成規則之二維陣列。
一維材料部分主要以晶種成長法製備不同形貌之金奈米粒子，已成功合成長度達2μm，且深寬比約70之奈米線，並以連續添加之方式達到簡易控制奈米棒/線長度之目標，控制範圍為50 nm至1.7μm，此外藉由實驗條件之控制，亦可合成其它形貌之粒子如米粒狀、T形、星狀與片狀三角板等結構，並以X光吸收光譜並配合理論計算之光譜模擬研究此晶種成長法之反應機制與成長過程。此外亦將一維之金奈米棒表面修飾抗體，藉由光譜之變化達到偵測相對應抗原之目的，並探討奈米金粒子形貌與表面修飾生物毒性之研究。

關鍵字

金屬奈米粒子；金；銀；鉑；形狀

並列摘要

We deal with the synthesis of the metal nanorattle with a pure metal shell by varying the experimental parameters. The galvanic replacement reaction has been applied to prepare metal nanoparticles with hollow structure. Hollow nanostructures were expected to have high performance. A facile procedure for the large-scale synthesis of hollow Pt nanosphere catalysts with nano-channels has been developed. Moreover, we have used the surface reduction of nanocubes of spinel cobalt oxide to demonstrate that magnetic alignments can also be extended to higher dimensions through forming superparamagnetic surfaces on pristine nanostructures.
On the other hand, we also emphasize on a new approach for fabrication of gold nanowires by controlling the volume of growth solution. The length of rods can be extended to 2 μm, and nanorods with aspect ratios of up to ~ 70 could be obtained. A modified seed-assisted growth method by serial addition of growth solution was employed to achieve the goal. The development approach was found to fabricate successfully 1-D gold nano rods/wires with a tunable size from 50 nm to 1.7 μm. A versatile route for the synthesis of gold nanostructures which could significantly alter the morphology of the resulting products (e.g., spherical nanoparticles, bipyramids, nanorods, nanowires, T- and star-shaped nanoparticles, and triangular nanoplates) by varying the experimental conditions has been demonstrated successfully. The theoretical simulation of X-ray absorption spectra further revealed that evolution of gold, ultra-fine small clusters presented after addition of reducing agent to growth solution. XAS results allow elucidation of the growth of gold and a proper scheme about the growth process.
We also demonstrated a rapid and sensitive approach to detect protein such as IgG using the localized surface plasmon absorption of the gold nanorods. The aggregation of gold nanorods which were preferentially oriented in a lateral (side-to-side and/or end-to-end) fashion driven by biorecognition process was observed. Moreover, the surface modification of gold nanorods can significantly decrease the cytotoxicity of nanorods, which would guide future application to a new direction.

並列關鍵字

metal nanoparticle；gold；silver；platinum；shape

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