Nano Energy Generated By Microfluidic Flow

Abstract

Energy harvesting is one of the most popular and important global issues for years. Through capturing or storing renewable energy, different energy-harvesting methods developed to provide additional power sources. In this work, a method to collect nano-scale energy by microfluidic flow was presented. Transferring microfluidic dynamic energy into electrical energy, we investigated the relationship between the extracted electrical current versus different electrode distances and the pH of an aqueous solution. The device was designed and implemented in a microfluidic channel with a gold-electrode grating. In the experimental testing, the flow rate was 300 μL/min. Based on the experimental results, the extracted output current was proportional to the electrode distance. The longer the distance (from 0.5 to 3 cm) was, the higher the output current (from 0.3 to 0.7 nA) obtained. In addition to the electrode-distance examinations, different aqueous solution with different pH value (from 5 to 10) were also investigated. To adjust the pH value of the solutions, hydrochloric acid (HCl) and sodium hydroxide (NaOH) were employed. In the pH-related experiments, the electrode distance was 3 cm and the flow rate was 300 μL/min. According to the experimental results, we can extract more electrical current (about 0.5 ~ 1.0 nA) with higher pH solution. In summary, this work demonstrated a potential method for energy harvesting. It could be used in different aqueous environment (ex. rain, river, marine etc.) or running water to generate current autonomously. This could be further integrated with applications of environmental monitoring.