그래핀 및 불화그래핀 기반 Au 나노아일랜드 SERS 기판의 형상 제어와 EM–CM 상호작용 분석 = Morphology Control and EM–CM Interaction Analysis of Au Nano-islands SERS Substrates Based on graphene and fluorinated graphene

다국어 초록 (Multilingual Abstract)

Surface Enhanced Raman Scattering (SERS) is a phenomenon in which Raman scattering signals are dramatically enhanced on the surfaces of noble metal nanostructures, and it has been widely applied in environmental analysis, biosensing, and food safety. However, conventional SERS substrate fabrication methods, including e-beam lithography, focused ion beam (FIB) lithography, and colloidal nanoparticle-based approaches, suffer from limitations such as poor reproducibility in controlling interparticle spacing, difficulty in large-area fabrication, and high processing costs.
In this study, Au was deposited on graphene (Gr) substrates to fabricate large-area SERS substrates with high reproducibility using a relatively simple process. To investigate the effects of surface chemical modification on Au growth behavior and SERS performance, Au was also deposited under identical conditions on fluorinated graphene (FG) substrates, in which fluorine atoms are bonded to graphene, enabling a comparative analysis. When Au was deposited under substrate heating conditions, Au grew into a nano-islands morphology, resulting in structures favorable for SERS enhancement.
On FG substrates, Au nano-islands exhibited a higher density and a more compact morphology due to fluorination-induced surface chemical changes, providing structurally favorable conditions for electromagnetic enhancement (EM). Nevertheless, the experimentally measured SERS intensity on FG substrates was lower than that on Gr substrates. This behavior is attributed to the reduced contribution of the chemical enhancement (CM) mechanism, arising from weakened π–π interactions, suppressed charge transfer between the molecule and the substrate, and altered adsorption behavior caused by fluorination. These results demonstrate that surface chemical modification plays a critical role in balancing EM and CM contributions in graphene-based SERS substrates, and provide meaningful insights into the design of two-dimensional material-based SERS platforms and the investigation of chemical enhancement mechanisms.

목차 (Table of Contents)

• 그림 목차 ⅱ
• 초록 ⅳ
• 제 1장 서론 1
• 제 2장 실험 방법 6
• 2.1 시약 및 재료 6
• 2.2 SERS 기판 제작 및 표면분석 7
• 2.2.1 SERS 기판 제작 7
• 2.2.2 SERS 기판 표면분석 10
• 2.2.3 라만 스펙트럼 측정 11
• 제 3장 결과 및 고찰 13
• 제 4장 결론 39
• 참고문헌 41