Effect of the wetting behavior of water droplets on the output of a water-droplet-based electricity generator

Abstract

Water-droplet-based electricity generators (DEGs) have attracted considerable attention owing to their simple metal substrate/dielectric/metal electrode structure and ability to generate high power instantaneously. However, their characteristics are significantly affected by the behavior of water droplets. In this study, to verify the relationship between water droplet movement and DEG output characteristics, we fabricated DEGs with two different structures. The electrodes were arranged vertically and horizontally with respect to the sliding direction of the water droplet, and DEG operation with different water droplet positions was verified. The results indicated that DEG output voltage varied according to water droplet behavior. Moreover, when the water droplet came in contact with an electrode, the wetting effect modified the shape of the droplet, thereby changing DEG output characteristics.