Effect of the spin crossover filler concentration on the performance of composite bilayer actuators

Abstract

Macroscopic, soft bilayer spin crossover@polymer actuators were fabricated by a blade casting technique using [Fe(NH2trz)3]SO4 spin crossover particles embedded in a P(VDF-TrFE) matrix. Incorporation of silver flakes in the second layer allowed for electro-thermal actuation via Joule heating. The speed and amplitude of the actuator bending movement, resulting from the expansion/contraction of the spin crossover particles on heating/cooling, were tested for different particle concentrations (15, 25, 33 and 50 wt%) under both open- and closed-loop controls. The capability of the actuators to embark charge and to follow a sinusoidal position was also investigated.