Enhanced Electrical Output in an Electrostatic Generator Using Charged Water

Electrostatic charging of water, particularly at the water–hydrophobic interface, continues to perplex researchers despite centuries of work. Recent advancements in energy harvesting, materials synthesis, and sensing employing electrohydrodynamic processes have generated renewed interest in the electrostatic charging of water. This work aims to understand the charging of water from an energy-harvesting perspective. We used a single-electrode electrostatic generator initially to demonstrate enhancement of the electric output with the addition of water. Through several control measurements, we established that the enhancement was a result of the electrostatic charging of water. The role of electrode wettability and pH on the electric output was studied. The effect of pH on the charging of water was correlated with the output voltage. The system was extended to a double-electrode electrostatic generator (DE-EG) to expand the applicability of the technique and increase the output. Using the DE-EG, we demonstrated the influence of an electric field on the charging of water. The electricity thus produced was used to power multiple light-emitting diodes. Furthermore, the technique was employed to treat wastewater containing a dye using a 3D-printed linear actuator. The insights presented are useful in enhancing the performance of water-based EGs and could help to better understand various electrohydrodynamic processes.