High conductivity graphite paste for radio frequency identification tag with wireless hydrogen sensor based on...

Radio frequency identification (RFID) technology has made significant strides in recent years, opening up a world of possibilities for various industries. However, to achieve success, reliable and accurate real-time data is crucial. One exciting application of RFID technology is fast and wireless detection of gases. Hydrogen, in particular, is considered a clean fuel. However, it is highly flammable, and detecting it quickly and accurately is challenging in various industries. In this regard, our research focuses on developing a high-conductivity graphite paste for RFID tags integrated with a wireless hydrogen sensor based on nano-CeO₂-Fe₂O₃-graphene oxide. In this work, we obtained a graphite paste using Ultra High Power (UHP) graphite electrodes with a high conductivity of 4.75 × 10⁵ S cm^-1 for non-metallic substrates and 4 × 10⁶ S cm^-1 with aluminum substrate. Furthermore, we incorporated a hydrogen gas detection sensor into the RFID tag utilizing graphene oxide and cerium oxide-iron oxide nanoparticles. The sensor demonstrated high sensitivity to low concentrations of H₂ gas (1 ppm), with stable and repeatable performance. The wireless sensing response was evaluated through reflection coefficient (S ₁₁) measurements, confirming effective impedance matching between the RFID chip and antenna. Through this research, we aim to promote the advancement of RFID technology by introducing a low-cost, battery-free sensing platform using graphite and nano-engineered materials, suitable for diverse industrial applications.