Design of passive coding RFID sensor tags for smart agriculture based on RGO-TiO₂-SWCNT electrode

A passive coding monopod antenna sensor (RFID) tag based on a composite material of titanium dioxide (TiO₂)/single-walled carbon nanotubes (SWCNT)/reduced graphene oxide (RGO) is studied. This sensor can be used to precisely measure light intensity and carbon dioxide concentration. Under the illumination of light with an intensity ranging from 4 to 18.1 klx, the input echo suffered a loss of - 21.88 dB. The response time of the tag to the light intensity was 9.8 s, and the recovery time was 19.2 s. The label generated a frequency point change of 124 MHZ at a carbon dioxide concentration ranging from 700 to 1900 ppm. The response time to the carbon dioxide concentration was 5.2 s, and the recovery time was 18.4 s. After testing and evaluation, this label has excellent stability, repeatability, and responsiveness under normal conditions.