Superhydrophobic and super-stretchable conductive composite hydrogels for human motion monitoring in complex condition

Abstract

With the advent of the information age, there is a growing demand for wearable sensing devices. Conventional hydrogels are a class of materials that can hold a large amount of water, with a three-dimensional network of hydrophilic polymerization chains inside. In remote areas or harsh environments, there is an urgent demand for a flexible sensor that is environmentally stable, wearable, and has high mechanical properties. Due to the hydrophilicity of the traditional hydrogel surface, it is easy to adsorb dust or be contaminated by liquid, which limits its further application. As a result, the superhydrophobic hydrogel F-PTD was designed using SiO2@PDA, F-HNT and PT hydrogel. TGA, XPS, SEM, FT-IR was used to characterize the structure of F-PTD, respectively. Based on the study of mussels, the adhesion property of polydopamine was utilized as an adhesion agent between organic–inorganic interfaces while improving the roughness of the hydrogel surface. The fabricated F-PTD superhydrophobic conductive hydrogels have excellent stretchability (Tensile Strain > 500 %), stable hydrophobicity (CA > 150°), and sensitive electrical conductivity (GF = 3.49). The contact angle of F-PTD is greater than 150° for tensile strains in the range of 0–350 %, and it maintains superhydrophobic under corrosive solutions with pH = 1–14. This enables F-PTD to perform the sensing function of detecting human body signals under complex environmental conditions, which has great potential for application in the field of underwater rescue, wearable electronics and human–computer interfaces.