# Synthesis and Studies of PAM-Ag-g/WS2/Ti3C2Tx Hydrogel and Its Possible Applications

## TL;DR

Scientists created a new stretchy, conductive hydrogel using nanomaterials that could be used as a flexible sensor for wearables.

## Contribution

A novel hybrid hydrogel with high conductivity and strain-sensing properties was developed using a WS2/Ti3C2Tx nanocomposite.

## Key findings

- The hydrogel showed gauge factors of 1.4 at low strain and 2.8 at higher strain.
- It had a fast response time of 2.17 s and recovery time of 0.46 s under cyclic stretching.
- The WS2/Ti3C2Tx interface significantly influenced the hydrogel's conductivity and electronic structure.

## Abstract

In this study, a new hybrid hydrogel based on PAM (polyacrylamide)-Ag-g/WS2/Ti3C2Tx was synthesized by radical polymerization using a conductive heterostructural nanocomposite WS2/Ti3C2Tx. The synergy between the polymer matrix and the interface between two-dimensional nanomaterials ensured the production of a hydrogel with high extensibility and conductivity, as well as sensory characteristics. The composite hydrogel exhibited excellent strain-sensing capabilities, with gauge factors of 1.4 at low strain and 2.8 at higher strain levels. In addition, the material showed a fast response time of 2.17 s and a short recovery time of 0.46 s under cyclic stretching, which confirms its high reliability and reproducibility. The integration of Ti3C2Tx and WS2 promoted the formation of a conductive network in the hydrogel structure, which simultaneously increased its mechanical strength and signal stability under variable loads. Measurements confirm some potential of the PAM-Ag-g/WS2/Ti3C2Tx composite hydrogel as a flexible wearable strain sensor. Based on measured numbers, we discussed the impact of the WS2/Ti3C2Tx interface on the Gauge factor and conductivity of the composite. Theoretical modeling demonstrates significant changes in the electronic structure of the WS2/Ti3C2Tx interface, and especially the WS2 surface, induced by substrate strain. Possible applications of the peculiar properties of PAM-Ag-g/WS2/Ti3C2Tx composite were proposed.