Fig. 1. (Color online) Human health detection system based on MXene/PEO flexible sensors. (a) Schematic diagram of the pulse monitoring system based on MXene/PEO flexible pressure sensor. (b) Schematic diagram of the structure of the MXene/PEO flexible pressure sensor. (c) Schematic diagram of the comparison of sensing range and sensitivity of different pressure sensors.

Fig. 2. (Color online) Pressure response of the MXene/PEO flexible sensor. (a) Schematic diagram of the MXene/PEO sensor at no load and under load. (b) The minimum pressure detection limit of the sensor. (c) Dynamic pressure-sensitive response of the MXene/PEO flexible sensor at different pressure levels. (d) Response and recovery time of the MXene/PEO flexible sensor. (e) and (f) I−V curves of the MXene/PEO-based flexible sensor at different pressures. (g) The sensitivity curves of the MXene/PEO flexible sensor at different pressures range from 44.34 kPa⁻¹ at 0.10 to 50 kPa and 12.99 KPa⁻¹ at 50 to 500 kPa.

Fig. 3. (Color online) Preparation, characterization and mechanical properties testing of MXene/PEO CNM. (a) Schematic diagram of the fabrication process of MXene/PEO CNM-based pressure sensors. (b) Scanning electron microscopy (SEM) image of MXene/PEO CNM prepared using 4 wt% PEO. (c) SEM image of MXene/PEO CNM prepared using 5 wt% PEO. (d) Pressure-sensitive response diagram of MXene/PEO flexible sensor at different bending angles. (e) Stability of MXene/PEO flexible sensors.

Fig. 4. (Color online) Human pulse monitoring system based on MXene/PEO flexible sensors. (a) Schematic diagram of a human pulse monitoring system. (b) In the resting state, the pulse signal detected by the pulse monitoring system. (c) After exercise, the pulse monitoring system detects the pulse signal.