High Performance Double Conductive Network Hydrogel Based on Soaking Strategy for Supercapacitors

Abstract High performance and high conductivity have always been important indicators for the application of hydrogels in the field of soft electronics. However, it is difficult for hydrogels to have both high conductivity and excellent mechanical properties. In this paper, a simple and feasible method is proposed, which allows polyvinyl alcohol to be embedded in the porous polyacrylamide chemical crosslinked network to form a structure of rich pores, and then soaked in salt solution to form a dense structure of hydrogels. In order to obtain good mechanical properties and electrical conductivity synchronously the hydrogel is soaked in KCl and NaCl solutions, respectively. However, different properties hydrogels are obtained after soaked in different salt solution, such as the strain of hydrogel after soaked in NaCl solution reached 750%, the conductivity of hydrogel after soaked in KCl solution is high (15.7 S m −1 ) and performed excellent conductivity even at low temperature (0 °C). In addition to the hydrogel after soaked in KCl solution showed 13.3 mF cm −2 high capacitance, the CV curve with regular shape and low temperature (0 °C) usage capacity when used as super capacitor. The conductive hydrogel can be used as artificial neural signal sensor, allowing produce artificial skin in medical field.