Vibrating ZnO–CNT nanotubes as pressure/stress sensors

ZnO–CNT nanotubes (NTs) have been fabricated by coating carbon nanotubes with zinc oxide (ZnO). One of their potential applications is the pressure/stress sensors based on their vibration sensitivity to external pressure. To implement the application, this paper aims to develop a mechanics model to quantify the pressure dependence of the NT vibration, identify the major factors that determine the pressure sensitivity and investigate the physics of the pressure-dependent vibration. The linear pressure dependence of the NT frequency is achieved with the pressure derivative rising rapidly with the radius of the core CNTs. The results provide essential information for the development and optimum design of the nanosensors, and offer useful guidance for further research on the mechanics of the hybrid nanostructures.

► A model is developed for the vibration of novel ZnO–CNT nanotubes (NTs) under pressure.
► High sensitivity of vibration to external pressure is achieved.
► The linear dependence on pressure is determined by the radius of CNTs but independent of ZnO thickness.
► The composite NTs are promising for electromechanical pressure nanosensors with high sensitivity.