Dual electro- and magneto-induced bending actuators of magnetite-loaded agarose ionogels.

Magnetic ionogels are a new kind of gel composites which combine the elastic properties from the swollen gel matrix and the magnetic properties from a magnetic filler. The dual electro-magneto-responsive agarose ionogels (AG IGels) were fabricated by a solution casting method using 1-butyl-3-methylimidazolium chloride [Bmim][Cl] as the ionic liquid solvent, and embedded with magnetite nanoparticles (Fe3 O4 NPs). The addition of Fe3 O4 NPs induced the high bending responses under applied electric and magnetic fields via the electronic polarization and magnetic interaction. The 3.0 wt.% Fe3 O4 /AG MagIGel showed the largest deflection distances relative to other magnetic gel composites; 14.92, 8.96, and 21.63 mm under the applied electric fields of 600 V/mm in silicone oil, 60 V/mm in air, and under the applied magnetic field of 600 G in air, respectively. The bending distances were of comparable in magnitudes to other electro-magneto-responsive materials. Thus, the fabricated Fe3 O4 /AG MagIGels are demonstrated here as potential for soft electric-magnetic actuator applications.