3. Conclusion

In conclusion, MXene/PDA film-based flexible pressure sensors with low health risk and high sensitivity are successfully prepared via dopamine intercalation polymerization. The dopamine molecule embedded in MXene nanosheets not only increases the layer spacing of MXene but also acts as a linker to form a 3D cross-linked structure, effectively improving the mechanical and pressure-sensing performance of the device. The sensor has excellent sensitivity (S1=24.7kPa-1; S2=138.8 kPa-1) and a relatively short response/recovery time (<100ms/<50 ms). Flexible pressure sensors can be safely applied to human skin to collect various human vital signs, including biological signs that show tiny deformations, for example, finger bending, pulse, facial expressions and vocalization. This demonstrates the immense potential of MXene/PDA-based sensing materials for artificial skin and wearable devices.