Bionic MXene based hybrid film design for an ultrasensitive piezoresistive pressure sensor

Abstract

• An ultrasensitive bionic sensor was rationally designed and realized. • The flexible bionic sensor was fabricated by molding and spraying methods. • A layer of PVA fiber was fabricated by the electrospinning method to further enhance the sensitivity of the bionic sensor. • The bionic sensor displays ultrahigh sensitivity of 403.46 kPa −1. • The bionic sensor possesses great potential applications in physiological signal test field. An ultrasensitive bionic MXene based piezoresistive pressure sensor was rationally designed and realized by molding the microstructure of the ginkgo leaf. Specifically, the core deformation part of the sensor under the applied force has been fabricated by imprinting the array-like microscopic shapes of the ginkgo leaves. The MXene-based pressure sensor was prepared by spraying the MXene onto the polydimethylsiloxane (PDMS) model film with the ginkgo leaf structure. To further enhance the sensitivity, a layer of polyvinyl alcohol (PVA) fiber fabricated by the electrospinning method was weaved between the MXene-based element and the electrodes in the sensor. Then, the obtained pressure sensor demonstrated ultrahigh sensitivity of 403.46 kPa −1 , short response time of 99.3 ms and extraordinary durability with 12,000 loading–unloading cycles. Furthermore, the microstructure change of the sensor under applied pressure was observed through the in-situ scanning electron microscope (SEM) experiment. Meanwhile, the pressure sensor also displays great potential applications ranging from the physiological signal test to the human–computer interaction field.