Multifunctional WS2&M-AgNPs superhydrophobic conductive sponges for application in various sensors

Abstract

Fabricating conductive materials based on sponges is applicable to many fields due to their outstanding performance. However, superhydrophobic conductive sponges are not only easily damaged by water but also have a complicated production process, which severely limit their working conditions and large-scale preparation. In this work, conductive sponges involving multiple superior characteristics of superhydrophobicity, excellent electrical conductivity, thermo-stability, and mechanical and chemical durability are fabricated based on WS₂ nanosheets and modified Ag nanoparticles (M-AgNPs) via a one-step method. More importantly, when immersed in water, the resistance of the WS₂&M-AgNPs superhydrophobic conductive sponge remained unchanged which is beneficial for adaptations in working conditions. In addition, in order to ensure the normal use of various sensors in the natural environment, WS₂&M-AgNPs conductive sponges possessed the important ability of thermo-stability and the resistance had little change in the temperature range 0 °C to 40 °C. Even after suffering 2400 compressions, the superhydrophobic sponges recovered their original shape and retained outstanding hydrophobicity, which highly prolonged the lifetime of the pedometer. The conductive sponges retained excellent hydrophobicity in the pH range 1 to 14. It was noted that the superhydrophobic conductive sponges showed a linear relationship between resistance and compressed distance. According to this linear relation, a pressure sensor fabricated using this sponge can measure multiple parameters such as weight and depth of water. Herein, a simple preparation method is provided to fabricate superhydrophobic conductive sponges, which expands the working conditions and may be a breakthrough for traditional sensor preparation.