We report carbide-derived carbon (CDC) based polymeric actuators for the low-voltage applications. The CDC-based
actuators have been designed and fabricated in combination with gold foil. The gold-foil-modified actuators exhibited
high frequency response and required remarkably low operating voltage (as low as ±0.25 V). Hot-pressed additional gold
layer (thickness 100 nm) ensures better conductivity of polymer supported CDC electrodes, while maintaining the
elasticity of actuator. Energy consumption of gold-foil-modified (CDC/gold) actuators increased only at higher
frequency values (f > 1 Hz), which is in good correlation with enhanced conductivity and improved charge delivery
capabilities. Electrochemical measurements of both actuators performed at small operating frequency values (f < 0.01
Hz) confirmed that there was no difference in consumed charge between conventional CDC and CDC/gold actuators.
Due to enhanced conductivity of CDC/gold actuators the accumulated charge increased at higher operating frequency
values, while initiating larger dimensional changes. For that reason, the CDC/gold actuators exhibited same deflection
rate at much lower potential applied. Electrochemical impedance measurements confirmed that relaxation time constant
of gold-foil-modified actuator decreased more than one order of magnitude, thus allowing faster charge/discharge cycles.
Gold-foil-modified actuators obtained the strain level of 2.2 % when rectangular voltage ±2 V was applied with
frequency 0.5 Hz. The compact design and similar working principle of multi-layered actuator also provides opportunity
to use actuator concurrently as energy storage device. From practical standpoint, this device concept can be easily
extended to actuator-capacitor hybrid designs for generation of energy efficient actuation.
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