本研究中，我們製備了一種輕薄可撓性雙層複合材料，利用其吸收電磁波的能力，改善無線射頻辨識(RFID)置於金屬上方失效的問題。材料選擇上，以聚二甲基矽氧烷(PDMS)為基材，利用其加工方便且易於成形的特性，透過混和三氧化二鐵(Fe2O3)以及聚四氟乙烯(PTFE)，分別製成兩種複合材料，利用Fe2O3層對電磁波的吸收，以及PTFE作為介電層，來阻絕吸收層對RFID晶片的干擾。此外我們使用化學法製備了氧化石墨烯(GO)粉末混和於Fe2O3粉末，在較低的粉末添加量上，增進其效益。電磁波進入PDMS複合材料後，首先是接觸第一層的PTFE，電磁波會受到較少的干擾進入第二層Fe2O3層，在經由Fe2O3層吸收部分電磁波的效應下，大幅減少被金屬表面反射影響的RFID訊號接收與發送，在50 wt% PTFE/PDMS複合材料加上70 wt% Fe2O3/PDMS複合材料的組合，原本被干擾的RFID晶片可由一分鐘讀取0次增強至一分鐘讀取289次。

In this work, we prepared a thin, flexible, double-layer composite material to lower the interference of the metal substrate to the radio frequency identification (RFID) placed on it through the absorption electromagnetic waves. Polydimethylsiloxane (PDMS) is used as the base material to prepare the layered composites with the structure of PTFE+PDMS/Fe2O3+PDMS. (Fe2O3+PDMS) layer is used to absorb electromagnetic waves and (PTFE+PDMS) layer is to create a gap between Fe2O3 layer and RFID tag. In addition, we used chemical methods to prepare graphene oxide (GO) powder which was mixed with Fe2O3 powder to increase the performance of the composites at a lower powder loading. While the electromagnetic wave enters the layered composite material, it contacts the first layer, that is the PTFE+PDMS layer, where the electromagnetic wave will receive less interference and enter the second layer of Fe2O3. Electromagnetic wave is partially absorbed by the second layer, as a result, reduce the intensity of the electromagnetic wave impinging on the metal surface, which increase the signal transfer between the RFID tag and reader. With the combination of 50 wt% PTFE composite material and 70 wt% Fe2O3 composite material, the originally interfered RFID chip can be enhanced to 289 reads per minute from nothing.

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