Multifunctional selectivity and mechanical properties have always been a focus of attention in the field of flexible sensors. In particular, the construction of biomimetic architecture for sensing materials can endow the fabricated sensors with intrinsic response features and extra derived functions. Here, inspired by the asymmetric structural features of human skin, w e have proposed a novel tannic acid (TA)-modified MXene-polyurethane (PU-TA@MXene) film with a bionic Janus architecture, which wa s prepared by gravity-driven self-assembly for the gradient dispersion of 2D TA@MXene nanosheets into a PU network. This obtained film reveals strong mechanical properties of a superior elongation at break of 2056.67% and an ultimate tensile strength of 50.78 MPa with self-healing performance. Moreover, the Janus architecture can lead to a selective multifunctional response of flexible sensors to directional bending, pressure and stretching. Combined with a machine learning module, the sensor wa s endowed with high recognition rates for force detection (96.1%). Meanwhile, direction identification in rescue operations and human movement monitoring can be realized by this sensor. This work offers essential research value and practical significance for the material structures, mechanical properties and application platforms of flexible sensors.

URL: https://onlinelibrary.wiley.com/doi/10.1002/adma.202302847?af=R