硒奈米刷之衍伸結構及電子束對於硒移除之效應

Several Derivatives of Selenium Nanobrush and the Electron Beam Effect on the Selenium Removal

徐勝泓(Hsu, Shenghung)

指導教授 ： 王崇人

國立中正大學/理學院/化學暨生物化學系/碩士(2012年)

摘要

以奈米硒作為模版的殼核結構物的合成概念已見於文獻，同時以物理或化學方式移除核的部分也是製備中空奈米結構物的途徑之一。過去實驗室成功地合成出了產率達100%的新型態硒奈米結構物：硒奈米刷(SeNB)，在我的研究中嘗試以SeNB作為模板進而設計其衍伸出的其他特殊材料的合成工作，包括複合結構奈米刷（主幹為硒，分支為二氧化矽）、硒奈米刷-二氧化矽核殼結構（SeNB@silica）、中空二氧化矽奈米刷結構物及其內部鍍奈米金粒子的複合型粒子等。在空殼內部進行反應也是文獻中較未提及的，因此我們也展示具有內部選擇性反應性結構物之合成設計。
本研究內容主要分為兩部分，第一部分的研究重點是硒奈米刷的分支移除製成主幹為硒，分支為二氧化矽的奈米刷。由於主幹與分支的移除溫度差異，利用熱移除搭配電子束的前處理可達到硒分支的選擇性移除並且保留結構中的二氧化矽，另一重點則是探討與展示電子束前處理對於二氧化矽及硒結構的效應。結果顯示加熱可將殼內的硒奈米刷幾乎完全（220°C）或選擇性移除其分支（~140°C）。我們亦發現電子束的照射，除了可進一步緻密化二氧化矽殼層結構之外，奈米硒核的移除溫度也會降低。此外，電子束照射過後的殼核結構粒子，相對未經處理的，選擇性移除較容易達成。
第二部分為硒奈米刷衍生物的合成，包括硒奈米刷-二氧化矽、硒奈米刷-二氧化鈦殼核結構物、空心二氧化矽奈米刷及其內部鍍金複合結構。以硒奈米刷做為模版，利用前驅物的水解縮合包覆在硒奈米刷外形成殼核結構，並達到殼層厚度的控制（~6 nm及19 nm）。硒奈米刷-二氧化矽殼核結構物經過熱移除內部硒核後，即形成二氧化矽空心奈米刷，另外，研究中也展示上述之二氧化矽空殼內側的硫醇官能基可以提供選擇性的化學反應，說明未來進行更進一步反應的可能性。以金離子還原吸附在二氧化矽空殼內為例，證明可選擇性地在中空殼的內壁上反應吸附奈米金粒子（8~11 nm）。

關鍵字

硒

並列摘要

Core-shell nanostructures based on nano-selenium were studied in articles, followed by physical or chemical removal of core was one of routes to synthesize hollow nanostructures. Here we present several complicated nanostructures derived from the selenium nanobrush(SeNB), including SeNB@silica core-shell nanostructures, hollow silica nanobrush and its interior nano-gold deposited nanocomposite. Interior deposition was rarely mentioned, therefore the design of selective reaction inside the shell was also demonstrated.
Our research could be divided into two parts, in first part, selective removal of selenium is achieved and forming the new nanocomposite with SiO2 branches and Selenium trunk. Base on the different melting point of branches and trunk, heat removal and electron beam(E-beam) pretreatment are adopted as the strategy to remove selenium in the branches. Moreover, the electron beam effect on the silica and selenium is also discussed. The result shows that by the heating process, branches in the SeNB structure can be selectively removed(~140°C), selenium core can also be nearly complete removed under similar process(~220°C). The illumination of E-beam is found to cause the density increase of silica and melting point depression of selenium.
Second part was the synthesis of SeNB derivatives, including SeNB@SiO2, SeNB@TiO2, hollow SiO2-NB and its nano-gold deposited nanocomposite. By the using of SeNB as chemical template, coating was formed throw sol-gel process and the shell thickness can be controlled in two dimension(~6 nm and 19 nm) . Hollow SiO2-NB is accomplished by heating the SeNB@SiO2 core-shell nanostructure to remove selenium core. In addition, the demonstration of interior nano-gold deposition was also presented. The mercapto group inside the silica shell provided a selective reaction to gold ion which shows the possibility for further reaction in the future. The gold nanoparticles(8~11 nm) are formed and found to adsorb inside the hollow SiO2-NB.

並列關鍵字

selenium

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