In Situ Preparation of Porous Humidity Sensitive Composite via a One-Stone-Two-Birds Strategy

•The porous ionogel humidity sensitive material was successfully fabricated with the aid of PAA as the template and humidity sensing component.•The humidity sensor based on the porous ionogel shows rapid response (1.2/0.6 s) to humidity change.•Various molecular weights PAA were applied to investigate PAA’s function in pore construction and humidity sensing.•The ultrafast-response humidity sensor can accurately record the human breath in real time, which is benefit for respiration data calculation.