石墨烯量子點在液態及高分子基材之光物理性質

Photophysical Properties of Graphene Quantum Dots in Liquid State and Polymer Matrix

陳渝彥(YU-YEN CHEN)

指導教授 ： 院繼祖

中原大學/理學院/物理學系/碩士(2022年)

https://doi.org/10.6840/cycu202201309

摘要

本論文旨在探討胺基官能化石墨烯量子點 ( Amine-functionalized GQDs, m-GQDs ) 的光學特性。利用具備苯環結構的小分子 ( Pyrene ) 以及三聚氰胺 ( Melamine )，利用微波 ( Microwave ) 加熱方式，以“由下而上”分子融合法來製作石墨烯量子點並以胺基來修飾其邊緣，這種胺基官能化之石墨烯量子點具有高的結晶品質及可控制的表面能態，同時具備寛廣的吸收光譜及低的非輻射複合過程。將胺基官能化石墨烯量子點分別溶解在四氫呋喃 ( Tetrahydrofuran, THF ) 與丙酮 ( Acetone ) 中可獲得長波長之光致發光 ( Photoluminescence, PL )。透過穿透式電子顯微鏡 ( Transmission Electron Microscope, TEM ) 以及原子力顯微鏡 ( Atomic Force Microscope, AFM ) 可觀察胺基官能化石墨烯量子點形貌。並以光譜量測了解其光學特性：透過激發光功率變化 ( Power-dependent ) 和溫度變化 ( Temperature-dependent ) 之放光光譜揭示官能化石墨烯量子點在特定極性溶劑中發光機制。我們發現 PL 發光機制可歸因於激子態與晶格震動的耦合。此外，我們還研究了石墨烯量子點在聚 ( 9-乙烯咔唑) ( poly(9-vinylcarbazole ), PVK ) 固體基質之光學特性，這將有利於進一步製備基於 GQDs 的電致發光元件。

關鍵字

石墨烯量子點 ； 邊緣化官能化 ； 芘 ； 三聚氰胺 ； 激發光功率變化 ； 溫度變化量測

並列摘要

This dissertation mainly discusses the optical properties of amine functionalized graphene quantum dots. Using four benzene ring structures of small molecules Pyrene and Melamine, by microwave synthesis, amine-edge-functionalized GQDs were prepared using bottom-up molecular fusion method, which can hold high crystalline structures with well-controlled surface states; they also exhibited broadband absorption and low non-radiative decay processes. The amine-edge-functionalized graphene quantum dots were dissolved in Tetrahydrofuran ( THF ) and Acetone respectively to obtain long-wavelength fluorescence. The morphology of the amine-functionalized graphene quantum dots was observed by Transmission Electron Microscope ( TEM ) and Atomic Force Microscope ( AFM ), and their optical properties were understood by spectroscopic measurement technology. Power-dependent and Temperature-dependent photoluminescence ( PL ) measurements were used to unravel the mechanism of the GQDs in solvent with distinct polarity. We found that the PL emission can be attributed to the excitonic states coupled to lattice vibrations. In addition, the PL properties of GQDs in PVK solid matrix were also studied, which would be beneficial for further preparing electroluminescent devices based on GQDs.

並列關鍵字

Graphene Quantum Dots ； Edge-functionalized ； Pyrene ； Melamine ； Power-dependent ； Temperature-dependent

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