Conception and Realization of Microwave Sensor for Efficient Hydrogen Detection

The demand for low-cost, energy-efficient, and environmentally-friendly sensors is driving innovations across diverse industries, including automotive, medical instrumentation, energy and chemical processing. In particular, hydrogen sensors play a pivotal role in ensuring the safety and reliability of energy systems, such as fuel cells and hydrogen storage technologies. This work introduces a novel microwave-based hydrogen sensor leveraging zinc oxide (ZnO) as a sensing material due to its high affinity for hydrogen. The sensor employs a resonant microstrip structure on a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$635-\mu \mathrm{m}$</tex>-thick RO6010 substrate, with copper metallization and localized ZnO incorporating in optimate regions. This design is optimized for sensitivity and performance using HFSS simulations. Operating at a resonant frequency around 3 GHz, the interaction of ZnO with hydrogen alters the electrical properties of the sensor, manifesting as measurable shifts in the resonant frequency. The sensor's compact design and integration of ZnO enable effective detection at low hydrogen concentrations, marking a significant advancement in the field of microwave planar sensors. Experimental validation demonstrates the sensor's high sensitivity, attributed to its optimized design, with a notable correlation between hydrogen concentration and frequency shifts. These results highlight the potential of ZnO-copper hybrid configurations in creating efficient and reliable sensors for green hydrogen applications. The proposed microwave hydrogen sensor aligns with UM6P's strategic focus on developing innovative technologies that address global energy challenges. By integrating advanced materials like ZnO into planar microwave circuits, this work paves the way for next-generation sensors capable of supporting sustainable energy transitions.