Hierarchical Asymmetric Complementary Bionic Structure for Highly Sensitive Pressure Sensor

Abstract Bionic structures are widely concerned in flexible sensors. However, there is a lack of research on the optimization of structure to improve the performance. Herein, two types of plant leaves with quite different surface structures, rose petal (RP) and paper mulberry (PM) leaf, are used to fabricate an asymmetric complementary structure. Under pressure, the microcones of PM can insert into the grooves of the RP microdome structures and can be bended under high pressure. Compared to that of PM–PM and RP–RP structures, the space for increasing the internal contact area of PM–RP structure is greatly enhanced, which improves the sensitivity and detection range of the sensor simultaneously. The hierarchical combination of stacked Ti 3 C 2 T x MXene film with nanoscale surface roughness and the micro PM–RP structure further improves the performance. The prepared sensor shows a sensitivity up to 84.79 kPa −1 (0–10 kPa), a wide pressure detection range of 0–100 kPa, and a short response time of 11 ms. It shows great application potential in wearable electronics. Meanwhile, a universal principle for the design of micro‐structure in pressure sensors is proposed, that is, reducing the initial contact resistance and enriching the approach for increasing the contact area.