本研究為使用層接式胜肽共價鍵結技術(Layer-by-layer and peptide reaction covalently anchored technique)將氧化石墨烯(GO)固定於聚酯(PET)塑膠基板上的金電極，製成可撓式二氧化氮氣體感測器。
首先以半胱胺鹽酸鹽(CH)胺基端接於金電極上，再使用胜肽鍵偶合劑(EDC/NHS)將GO共價鍵結於已經以CH修飾的電極，再利用還原劑，硼氫化鈉(NaBH4)同步將修飾GO薄膜還原成還原氧化石墨烯(RGO)薄膜。
利用原子力顯微鏡(AFM)、場發射掃描式電子顯微鏡(FE-SEM)、電化學交流阻抗分析儀(EIS)與傅利葉轉換紅外光譜儀(FTIR)分析此可撓式奈米複合薄膜的表面結構、材料特性之特徵分析。
此可撓式氣體感測元件對於二氧化氮(NO2)氣體明顯有良好的感度、長期穩定性佳，並具有可撓性、製備簡單等優點。
Novel flexible NO2 gas sensors were fabricated by covalently bonding graphene oxide (GO) to a gold electrode on a plastic substrate using a peptide chemical protocol and then reducing in-situ GO film to a reduced GO (RGO) film. A pair of comb-like Au electrodes on a polyethylene terephthalate (PET) substrate were pretreated with cysteamine hydrochloride (CH) and then reacted with GO using N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) as the peptide coupling reagent, before undergoing a final reduction by sodium borohydride (NaBH4). The anchored RGO film was characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FTIR). The gas sensing properties, including sensitivity, sensing linearity, reproducibility, response time, recovery time, cross-sensitivity effects and long-term stability, were investigated. Interfering gas NH3 affected the limit of detection (LOD) of a target NO2 gas in a real-world binary gas mixture. The flexible NO2 gas sensor exhibited a strong response and good flexibility that exceeded that of sensors that were made from graphene film grown by chemical vapor deposition method (CVD-graphene) at room temperature. Its use is practical because it is so easy to fabricate.
