Surface engineered ZnO nanorods array for multidirectional force detection

Tactile sensors serve as the cornerstone of modern technology by mimicking human tactile perception and delivering precise and diverse mechanical feedback for advanced applications in robotics, medical equipment, and virtual reality. However, current research predominantly concentrates on the detection of normal forces, while the accurate recognition and decoupling of multidirectional force pairs remains a significant challenge. In this study, we present a multidirectional force sensor based on surface-engineered zinc oxide nanorods (ZnO NRs) arrays coupled with a transverse force-to-vertical force conversion structure. Surface modification with cuprous oxide (Cu2O) substantially boosts the piezoelectric output of ZnO NRs, achieving a sensitivity of 17.25?nA?MPa?1, which is about three times greater than that of pure ZnO. Experimental results elucidate the mechanism underlying this enhancement, highlighting the pivotal role of surface-engineered heterojunctions. On this basis, a prototype demonstrates the capability to detect transverse forces in 12 directions spanning a 360° range, thus validating its multidirectional force detection performance. This work provides a new strategy for designing multidirectional force sensors, offering considerable potential for applications in human-machine interaction and beyond.
[来源：中国聚合物网]