Enhanced-Performance Wireless Conformal "Smart Skins" Utilizing Inkjet-Printed Carbon-Nanostructures

This paper introduces for the first time the integration of a UHF radio frequency identification (RFID) antenna with reduced graphene oxide (rGO), developed using direct-write techniques and utilizing an RFID chip for chemical gas detection. The module is realized by inkjet printing on a low-cost paper-based substrate, and the RFID tag is designed for the North America UHF RFID band. The electrical impedance of the rGO thin film changes in the presence of very small quantities of certain toxic gases, resulting in a variation of the backscattered power level which is easily detected by the RFID reader to realize reliable wireless toxic gas sensing. The inkjet printed RFID tag demonstrated a change in backscattered power of 9.18% upon exposure of 40 ppm NO2 for 5 minutes.