LAUSR

Recent years have seen the rapid development of electronic skin for autonomous robotics and human-machine interaction. As a result, the demand for flexible pressure sensors as the critical sensing element in electronic skin is also increasing. These sensors need to feature high sensitivity, short response time, low detection limit, large measurement range, and so on. In this paper, inspired from the cobweb in nature, we creatively proposed a piezoresistive pressure sensor which is developed by forming a cobweb-like network made of Zinc octaethylphorphyrin (ZnOEP)/Carbon Nanotube (CNT) hybrid on an array of nonuniform polydimethylsiloxane (PDMS) microposts. The hybrid material exhibits excellent adhesion to PDMS, benefitting from ZnOEP's low Young's modulus and the nonpolar bonding between ZnOEP and PDMS, such that no delamination and resistance variation is found after thousands of cycles of bending and twisting. With the biomimetic overhang morphology of the ZnOEP/CNT network on the nonuniform micropost array, we realized a pressure sensor with an ultrahigh sensitivity of 39.4 kPa-1, a super-fast response time of 3 ms, a low detection limit of 10 Pa, and a reproducible response after 5000 cycles of pressure loading/unloading. The sensor can be employed for a variety of applications, including wrist pulses measurement, sound level detection, mechanical vibration monitoring, etc., proving its great potential for use in wearable electronics and autonomous robotics.