受惠於奈米晶體特殊的光學、電學與化學反應性，使奈米晶體在各種應用上極具潛力，例如奈米晶體的電子於光照下產生之極化現象，亦稱局部表面電漿子共振 (localized surface plasmon resonance, LSPR)並且於奈米晶體表面產生強的電磁場。由於電子於共振情況下能獲得能量而形成”熱電子” ，這些熱電子被廣泛用於光化學領域。由於這些特殊的奈米晶體性質，以下將探討奈米晶體於三個不同應用領域之表現:。
第一部份，我們利用晶種介導與電漿子介導法於奈米晶體模板上形成高度異相之反應環境，進而合成具有可控制形貌與組成之雙金屬和半導體-金屬奈米晶體。有別於傳統晶種介導合成法以保護劑調控反應環境，此法因利用電漿子介導改變奈米晶體表面電磁場分佈與調整奈米晶體於高分基質之位置來改變晶種暴露於反應溶液之面積，使奈米晶體周圍具高度異向性反應環境。本研究藉由此高度異向性反應環境可以成功合成出具有特殊結構之非均質雙成分之奈米晶體，如花邊狀、頂角具凸出結構之Au-Ag合金奈米晶體及花瓣狀Ag2S-Ag奈米晶體。這種新的合成方法有望合成各種具有良好形貌和合成多組分奈米晶體達到客製化的性能已於各種潛在應用如催化、光伏打元件、傳感器、醫學成像、光熱治療等。
第二部份，以上述於高分子基質上所合成的非均質奈米晶體作為4-硝基苯酚 (4-nitrophenol, 4-NP )之還原觸媒。結果顯示(1)以埋入高分子基質的非均質奈米晶體做非勻相催化(heterogeneous catalysis)反應，可提高再使用之穩定性; (2) 非均質奈米晶體的觸媒活性與非均質材料各成分間的協同效應有關，此效應可透過調控非均質奈米晶體的組成分及形貌來調整。
第三部份，電漿子奈米晶體藉由逐層堆疊法導入光伏打元件中作為主動層。逐層沉積法提供一快速且簡便的方法製備光伏打元件。以電漿子奈米晶體作為主動層提供電子，可透過熱電子注入(hot electron injection)及電漿子共振近場增強效應 (LSPR near-field enhancement effect)來增強光伏打元件之效能，。其結果顯示以電漿子奈米晶體形成之光伏打元件之效能與(1)電漿子晶體之組成與形狀與(2)激發光強度與波長有關。

Nanocrystals are promising materials with great potential for various applications because of their special optical, electrical, and catalyst properties. For example, localized surface plasmon resonances (LSPRs) occur on the plasmon nanocrystal which results from the phenomenon of electron polarization around the nanocrystals under irradiation. The phenomenon of polarization leads to a strong electromagnetic field around the plasmon nanocrystals. Due to these oscillating electrons receiving energy from irradiation and generating high-energy “hot electrons”, these nanocrystals are widely used in many photochemical fields. Based on these unique properties as mentioned previously, this study focuses on the performance of nanocrystals in various applications as follows:
In the first part, we integrated the seed-mediated and plasmon-mediated photochemistry methods for fabricating bimetallic and semiconductor-metal nanocrystals with controllable morphology and composition of the nanocrystal resulting from the highly anisotropic reaction environment around the nanocrystal. Different from the traditional methods of using the protecting agent to control the reaction environment, the highly anisotropic reaction environment around template nanocrystals is caused by the changes of the electromagnetic fields distribution around them under plasmon-induced effect and the exposure area in the reaction solution, which can be adjusted by controlling the position of nanocrystals in the polymer matrix. Here, the highly heterogenous bi-component nanocrystals, such as edge-flower like Au-Ag nanocrystals, pump-corner half-cage Au-Ag nanocrystals, and flower-like Ag2S-Ag nanocrystals, can be successfully fabricated in the highly anisotropic reaction environment formed around the template nanocrystals. This new synthetic method should be able to be used to fabricate various multicomponent nanocrystals with desirable functions for potential applications, such as photocatalysts, chemical /biosensors, and biomedicine et.al.
Secondly, the as-made heterogeneous nanocrystals on the polymer matrix are used as the catalysts for the reduction of 4-nitrophenol(4-NP). The results show that: (1) heterogeneous nanocrystals on polymer matrix as heterogeneous catalysts can enhance the stability of reuse ; (2)the reactivity of heterogeneous nanocrystals as catalysts depends on the synergistic effect between the components on nanocrystals, which can be adjusted by changing the composition and morphology of nanocrystals. Furthermore, these heterogeneous nanocrystals can be developed into a photocatalyst due to their LSPR properties.

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