A Dual‐Responsive Magnetoactive and Electro–Ionic Soft Actuator Derived from a Nickel‐Based Metal–Organic Framework

Abstract

There is growing demand for multiresponsive soft actuators for the realization of natural, safe, and complex motions in robotic interactions. In particular, soft actuators simultaneously stimulated by electrical and magnetic fields are always under development owing to their simple controllability and reliability during operation. Herein, magnetically and electrically driven dual‐responsive soft actuators (MESAs) derived from novel nickel‐based metal–organic frameworks (Ni‐MOFs‐700C), are reported. Nanoscale Ni‐MOFs‐700C has excellent electrochemical and magnetic properties that allow it to be used as a multifunctional material under both magnetoactive and electro‐ionic actuations. The dual‐responsive MESA exhibits a bending displacement of 30 mm and an ultrafast rising time of 1.5 s under a very low input voltage of 1 V and also exerts a bending deflection of 12.5 mm at 50 mT under a high excitation frequency of 5 Hz. By utilizing a dual‐responsive MESA, the hovering motion of a hummingbird robot is demonstrated under magnetic and electrical stimuli.

Controllable Multimodal Actuation in Fully Printed Ultrathin Micro-Patterned Electrochemical Actuators

“…We have chosen PEDOT:PSS and Nafion in our study because they are biocompatible, widely investigated, and readily available in dispersions. Nevertheless, recently developed materials were shown to dramatically enhance the ionic conductivity in the actuator and the electronic conductivity and the charge storage capacity of the electrodes, leading to significantly improved actuation. ,,, Microfabrication of these materials and the development of new materials with our AJP approach will potentially create open-air microactuators and multisegment actuators with more impressive performance.…”

“…A PEDOT/Nafion/PEDOT actuator fabricated by polymerization on a surface-treated Nafion membrane achieved ∼0.32 rad deflection under 1.5 V step input but required more than 80 s to get close to equilibrium . In more recent papers, the PEDOT:PSS/Nafion/PEDOT:PSS configuration was often reported alongside higher-performance ECAs as a benchmark for comparison. ,,− From the data provided by Yu et al, a PEDOT:PSS/Nafion/PEDOT:PSS actuator made by drop casting had an equilibrium time >10 s, a θ pp of ∼0.1 rad under 0.1 Hz, ±0.5 V square wave input, and no actuation performance at frequencies above 2 Hz.…”

Hygrothermic Wood Actuated Robotic Hand

“…The present actuators are mostly produced by polymers, [27] elastomers, [28] hydrogels, [29] shape memory alloys, [30] liquid crystals, [31,32] fibers, and films based on polysaccharide or protein components. [33][34][35] Active materials which can improve the conversion properties of actuators, such as MXenes, [16,34] carbon nanotubes, [9] graphene, [36] metalorganic frameworks, [37] and ferro ferric oxide nanoparticles [38] are generally introduced. Although some structural design and performance improvements have been reported for such actuators, there are still several remaining challenges that need to be further addressed: 1) The cost of polymer and nanomaterials is usually high, which restricts the use of actuators on a large scale.…”

Recent Advances in Electrically Driven Soft Actuators across Dimensional Scales from 2D to 3D

“…[136][137][138][139][140] These kinds of actuators convert electrical energy into mechanical energy via electrochemical processes. [136,[141][142][143] They were usually fabricated into a sheet shape that consists of two electrode layers and an electrolyte layer. The materials of the electromechanical actuators can be divided into three main types: metal-based, nanocarbon-based, and polymer-based, which are actuated based on different principles including changes in the lattice parameters, changes in valence states, chemical adsorption of ions, intercalation and delamination of ions, inhalation and detachment of ions, and inhalation and detachment of H 2 O molecules.…”