Study on characteristics of the electric‐field‐sensitive hydrogel inspired by jelly in the ampullae of Lorenzini of elasmobranchs

Abstract The elasmobranchs can sense the weak electric field signals of marine environment and other lives to adjust follow‐up activities by the jelly in their ampullae of Lorenzini, which provides a new research route for the development of ocean exploration, locating of underwater object, underwater navigation and communication. Inspired by such a characteristic of jelly, this paper presents a novel electric‐field‐sensitive hydrogel in response to weak electric field stimuli in surroundings. The hydrogel is made from I‐carrageenan (IC) and cellulose nanocrystals (CNCs) by the way of blending. The effects of CNCs on the performances of hydrogels have been investigated via the characterization of both IC/CNC blending hydrogel and pure IC hydrogel. Swelling experiments show that the equilibrium swelling ratio of hydrogel is positively related to the mass ratio of IC to CNCs. Electric field sensitivity experiments indicates that the IC/CNC blending hydrogel has a higher sensitivity than the pure IC hydrogel by comparing the bending angles of hydrogels under different electric fields, and the maximum bending angle, 0.5°, of blending hydrogel remains under the 1 mV/cm electric field. The blending hydrogel sensitive to weak electric field stimuli in this paper may provide an alternative strategy to develop intelligent response‐type materials for applications of efficient underwater sensors and actuators.