Nanoparticle-functionalized microsensors for room-temperature hydrogen detection

Selective sensing of trace hydrogen gas is highly desirable in leak detection applications, and it has recently come to the fore to an even larger degree due to the great potential of hydrogen in the current energy transition. One difficulty of room-temperature hydrogen sensing in an open environment is the potential interference from multiple other analytes, including water vapor, especially in high-humidity environments. To develop a high-responsivity, selective hydrogen gas sensor, ultrathin palladium nanosheets (PdNS) were synthesized using a hydrothermal method. Then, the PdNS were utilized as the chemical recognition layers in gravimetric resonant gas sensors for the real-time detection of hydrogen at room temperature. The nanoscale structure of the PdNS provides the material with a high amount of functional surface area; in turn, this allowed for significant surface-analyte interactions and high-performance sensing. Importantly, the PdNS active layer can selectively sense hydrogen gas in the presence of multiple interfering gases (e.g., acetone, alcohols, and water vapor) in the concentration range of 1–5% in both nitrogen and air environments. Therefore, this sensor system may potentially be of interest for future industrial applications regarding the safe handling of hydrogen gas. Graphical abstract