Natural rubber-nanodiamond films for the minimisation of losses in dielectric energy harvesters

Dielectric elastomer generators (DEGs) belong to the new and promising class of devices harvesting energy from ambient sources, e.g., ocean waves. However, the efficiency and energy output of the existing DEG prototypes are often limited, for example, by high material-related losses of the utilised dielectric elastomers. Therefore, despite the recent advances in the DEG research, minimisation of losses of elastomeric material for DEG application is still in demand. The present study focuses on the material-related losses of natural rubber (NR) and shows the possibility to decrease the low-frequency losses by the addition of nanodiamonds. The post-treatment of the films, namely leaching and acetone extraction, allows reducing the losses even more – by almost 25% for NR. Moreover, acetone treatment results in a positive effect on the mechanical properties of the samples, as well as reduced viscous losses and improved stress relaxation behaviour.