表面電漿共振(surface plasmon resonance, SPR)技術可即時監測金屬-電介質表面折射率變化的特性。本研究利用SPR即時監測以電化學技術還原氧化石墨烯(Graphene oxide, GO)的去氧過程，藉由SPR角位移量的改變，判斷出不同還原時間下的氧含量，達到即時調控GO之碳氧比與能隙。
本研究採用三種不同的實驗方式還原GO，分別為實驗一：以循環伏安法(cyclic voltammetry, CV)還原GO膜；實驗二：以定電壓還原GO膜；實驗三：以CV還原GO混合溶液。前兩個實驗以胱胺(Cystamine, Cys)作為連接層，在金膜上形成穩定共價之GO膜，並分別以不同電化學模式CV與恆定電壓法進行還原。第三個實驗則是將GO溶液與NaCl電解質混合，形成GO混合溶液，之後再以CV法進行還原。
不同還原程度之GO膜，將採用X射線光電子能譜(X-ray photoelectron spectroscopy, XPS)與Raman光譜分析特性，並利用XPS的結果搭配Essential Macleod模擬軟體計算出不同還原程度之GO折射率。不同還原程度之GO混合溶液則採用光致螢光光譜(Photoluminescence, PL)與雙光束分光光譜儀系統(UV-Vis)進行分析。
本研究利用實驗與模擬結果證明了利用電化學表面電漿共振(Electrochemical surface plasmon resonance, EC-SPR)技術可以即時監測與逐步調控GO之碳氧比。使用定電壓還原在120秒內，可利用SPR技術調控GO之碳氧比，由4.10至71.41，折射率則可由1.7 + i0.17調控至1.83 + i0.42。而GO混合溶液則可用CV法調控GO之放光波長由470~600 nm。

Surface plasma resonance (SPR) technology is capable of detecting changes in refractive index near the surface of dielectric-metal interface. This paper used SPR technology real-time detection deoxidization process of graphene oxide (GO) converted to reduced graphene oxide (rGO) by electrochemical method.
In this study, we have three different experimental methods to reduction GO, Experiment I：Used cyclic voltammetry (CV) reduction GO film；Experiment II：Used constant voltage reduction GO film；Experiment III：Used CV reduction GO mixed solution. The first two experiments used cysteamine (Cys) connection a gold film and GO layer to form a stable covalent GO film. Then we used CV or constant voltage reduction GO film. The third experiment, GO solution is mixed with NaCl electrolyte to form a mixed solution of GO and reduction by CV.
We will analysis the rGO film by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Then, we can use of XPS results with Essential Macleod simulation software to calculate the rGO refractive index. GO mixed solution analysis by photoluminescence (PL) and double beam spectrophotometer (UV-Vis)
Experimental results demonstrate that the electrochemical surface plasmon resonance (EC-SPR) signal can quantitatively detect in real time and tunable C/O ratios. In constant voltage method, GO converts to rGO changes the C/O ratio from 4.10 into 71.41 and refractive index changes from 1.7 + i0.17 to 1.83 + i0.42. While the mixed solution of GO can tunable luminescence wavelength from 470~600 nm by CV method.

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