Solvent effects on carbide-derived-carbon trilayer bending actuators

Abstract Bending actuators were prepared by depositing carbide-derived carbon, a material typical for electric double layer capacitors, on both sides of poly-vinylidenefluoride membranes, forming CDC-trilayers. Their actuation properties were studied using 0.5 M solutions of lithium perchlorate (LiClO 4 ) in different solvents: water, ethylene glycol, acetonitrile, and propylene carbonate. The goal of this work was to study the actuation mechanism, charging-discharging properties in these solvents, as well as to establish the optimal solvent for maximum bending displacement. It was found that while the actuation direction was the same for all solvents, pointing to similar mechanism, the exchanged charge and the displacement differed considerably. Moreover, the highest specific capacitance found in ethylene glycol did not bring along the highest displacement, neither was the highest exchanged charge of propylene carbonate the most efficient option, the acetonitrile was the clear winner. The available electrochemical windows for the reversible charging also differed considerably.