利用聚集螢光增強機制提高銅奈米團簇光學性質

以配位共價鍵穩定的銅奈米團簇可利用簡易水合成方法製作，且實驗方式不含有毒的前驅物和低成本。此外，它們還有一些有趣且可探討的光物理特性，例如：可調控的螢光光譜、大的Stokes shift、分子間鍵結-金屬電子轉移態。不幸的，低量子產率及較差的穩定度阻礙了它的實際應用效益。為了解決這些問題，本文利用幾種光譜技術及材料檢定技術研究以穀胱甘肽分子鍵結穩定的銅奈米團簇加入不同的基質材料的光物理特性。與原始銅奈米團簇溶液比較下，發現藉由溶膠-凝膠法所製作的二氧化矽-銅奈米團簇的量子產率及穩定性都大大的提高；量子產率的提高伴隨著螢光生命期的增加，表示抑制了非輻射覆合的途徑，也呈現銅奈米團簇與基質間的表面鍵結扮演著重要的作用力以控制其光物理特性。

關鍵字

銅奈米團簇；聚集誘導放光

並列摘要

Ligand-stabilized copper nanoclusters (CuNCs) can be simply prepared using mild aqueous synthesis based on low-cost and nontoxic precursors. In addition, they possess some fascinating photophysical properties, such as tunable photoluminescence (PL), large Stokes shift, and intramolecular ligand-metal charge transfer states. Unfortunately, low PL quantum yields (QYs) and poor stability largely hinder their practical utility. To address these issues, in this thesis, the photophysical properties of glutathione-stabilized CuNCs (GSH-CuNCs) embedded in the different matrices were studied by several spectroscopic techniques and materials characterization. We found that both PL QYs and stability can be largely enhanced for GSH-CuNCs incorporated with sol-gel-derived mesoporous silica, as compared with that of pristine CuNCs in solution. The QY enhancement is accompanied with the increase of the PL lifetime, indicating the suppression of nonradiative decay processes. It is also revealed that interfacial bonding between GSH-CuNCs and surrounding matrix plays an important role in determining their photophysical properties.