近年來相關實驗及理論計算之研究指出，石墨烯量子點此零維度奈米材料其具有獨特的物理、化學及光學特性，逐漸受到各界注視。由於其具有石墨烯之奈米結構，因而保有石墨烯優越的物理化學性質，包括大比表面積、高電子遷移率、低毒性和化學穩定性等。更當其尺寸小於100 nm時，電子會受量子侷限效應和邊界效應之影響因而產生獨特的光致發光性質。這些優點使得石墨烯量子點非常有潛力運用於開發生物分子感測器之應用。表面增強拉曼散射是一種高靈敏度檢測技術，可用來大幅增強待測物的拉曼訊號。多數的研究證實了貴重金屬如金和銀及石墨烯相關碳材皆能作為表面增強拉曼散射基材的可行性及潛力。 但相較於石墨烯，石墨烯量子點應用於表面增強拉曼散射上之探討仍不夠完整。

在此研究中採用具有不同性質之石墨烯量子點來探討的石墨烯量子點的表面增強拉曼散射特性。 此外將石墨烯量子點與金屬奈米粒子複合後，將能夠大幅的提升材料的表面增強拉曼散射活性。在此研究中透過使用大氣常壓微電漿輔助電化學法來達到快速合成石墨烯量子點-銀奈米粒子複合物。在一系列的材料鑑定過後，微電漿電化學輔助法可以成功得將銀奈米粒子附載到石墨烯量子點的表面上，形成具有異質二聚體奈米結構的複合材料。光致發光光譜及螢光壽命分析證實，在石墨烯量子點-銀奈米粒子複合物中有非輻射螢光共振能量轉移的現象發生。此研究了進一步探討具有不同螢光共振能量轉移效率的石墨烯量子點-銀奈米粒子複合物對表面增強拉曼散射活性之影響。

Recently experimental and theoretical works have reported that graphene quantum dots (GQDs), a unique form of a zero-dimensional nanostructure, and their exceptional properties make them promising in biosensing applications. Surface-enhanced Raman scattering(SERS) is an ultra-sensitive analytical technique for bio-molecules detection. While the potential of SPR metals (e.g. Au and Ag) and graphene for SERS has been demonstrated, but the work of GQDs applied as SERS substrates is still lacking. Here we reported the rational design to develop GQD-based SERS active substrate.
Furthermore, modified GQD with metal nanostructures will lead to important advance for SERS-based detection. Here we demonstrate a facile synthesis of GQD-AgNP nanohybrids by using the atmospheric-pressure microplasma-assisted electrochemistry. Detailed nanomaterial characterizations including transmission electron microscopy, UV/Vis spectroscopy show that the microplasma-assisted electrochemical reaction can successfully grow Ag nanoparticles (AgNP) onto the GQD surfaces to form the GQD-AgNP nanohybrids with heterodimeric nanostructures within the minute scale. Besides, the photoluminescence (PL) optical study and lifetime analysis of GQDs and GQD-AgNP indicated that the non-radiative fluorescence resonance energy transfer involved in the GQD-AgNP nanohybrids.
In the systematic Raman study, R6G is selected as the Raman probe molecules. First, we compare the SERS property of three kinds of GQDs with different photoluminescence property (e.g. different emission wavelength), Raman results show that SERS performance of GQDs is highly influenced by the molecular adsorption ability. The as-produced GQD-AgNP nanohybrids shows superior SERS performance with high enhancement factor (EF) around 1x10^8.

We further studied the GQD-AgNP nanohybrids with different FRET efficiency. The results revealed that FRET of the as-produced GQD-AgNP nanohybrids is the dominant factor to SERS properties in our study.

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