Ultra-sensitive hydrogen sensor based on powder aerosol deposited WO₃ with amorphous matrix encapsulated nanocrystalline

Hydrogen now transcends its conventional energy carrier role, serving as a critical alert medium for lithium-battery thermal runaway alerts. This new application imposes stringent requirements on hydrogen sensors, primarily involving the precise quantification at trace concentrations and the rapid response upon exposing to high-concentration hydrogen. To address these emerging detection demands, we engineer a WO₃-based sensor via powder aerosol deposition method. This approach exploits synergistic hammer-etching effects during impact consolidation, yielding amorphous matrix encapsulated nanocrystalline WO₃. Optimized devices exhibit exceptional performance: broad detection range (100 ppb-20,000 ppm), record sensitivity (>7 ×10⁵ @ 2 vol% H₂), ultrafast response (≤ 0.4 s), and long-term stability. These advances demonstrate significant potential for battery safety monitoring and validate aerosol deposition for next-generation gas sensor fabrication.