• • The Pt–SnO2–SiO2/SiO2 sensor achieves a 157-fold response increase to 1000 ppb NO2 at 25 °C, enabling ppb-level detection for wearable environmental monitoring.
• • After 10000 bending cycles at a curvature radius of 2 mm, the sensor retains its robust response without sensitivity degradation, demonstrating mechanical durability essential for on-body applications.
• • The all-inorganic three-dimensional porous network provides high breathability and thermal stability, overcoming the limited gas permeability and thermal constraints (300–400 °C aging) of organic substrates such as PET, PI, and PVDF.
• • The amorphous SiO2 nanofiber substrate eliminates the weak van der Waals bonding that causes delamination in traditional flexible MOS sensors, ensuring stable operation under repeated deformation.