Fig. 3: Extremely high-sensing resolution of the graded intrafillable architecture (GIA)-based iontronic pressure sensor.

a Schematic illustration of the response of the iontronic pressure sensor to low and high pressure, and detection of micro pressure under high pressure. b–d Detection of micro pressure under loading pressures of b 3 kPa, c 30 kPa, and d 300 kPa, respectively. e Detection of different micro pressure objects placed on three concrete bricks weighing 320 kPa. f Capacitance signals corresponding to panel e. g Experimental set-up of a car with a GIA-based iontronic pressure sensor bonded under a rear tire, the test frequency is 10 kHz. h Capacitance signals corresponding to a loaded, unloaded, and reloaded 1.7 kg bag of paper towels in the trunk of the car. i Capacitance signals corresponding to a 50 kg female passenger getting into and out of the car. The test frequency is 10 kHz.