Investigation of the Effect of Electrode Placement and Tilt Angle on Induced Voltage by Electrolyte Flowing over Graphene

• Main Authors: Yu-YuanSun, 孫于淵
• Other Authors: Ruey-Jen Yang
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/rgb43b

碩士 === 國立成功大學 === 工程科學系 === 107 === The extraction of energy from water in the natural environment is a very important trend in energy harvesting. It provides energy demand for human needs and for self-powers in small electronic devices. Currently, graphene is a relatively new two-dimensional material that may provide energy extraction because of its excellent physical properties. In order to understand the optimal induced voltage for the liquid flow over the graphene, the placement of the electrode and the tilt angle of the graphene are important factors. This thesis mainly discusses the influence of the electrode placement and tilt angle on the induced voltage from sodium chloride electrolyte flowing over the graphene. First, the electrode was coated with silver gel to investigate its induced current for both parallel flow direction and vertical flow direction to the electrode. This study has shown that the parallel flow arrangement produces higher induced voltages since the cations in the electrolyte are in the same direction as the electron current. Therefore we utilized the parallel flow direction of the electrodes to investigate the liquid flow over the long and short sides of the graphene with the same total areas exposed to the flow. This study has shown that flows through the long side of the electrode, under the higher concentration of electrons in the cation and graphene in the solution per unit time, produce a better voltage response. Finally, through the self-made silver chloride electrode, the trend of the graphene induced voltage of the electrolyte flowing at different tilt angles and different flow rates is investigated. This study found that increasing the tilt angle from 20° to 45° increased the flow rate. In addition, the charging time and the discharging time were gradually shortened. The shorter the charging and discharging times, the higher the amount of charge collected per unit time, and the optimal induced voltage occurred at an angle of 45°. On the other hand, when the tilt angle increased from 45° to 60° the voltage decreased. This is because the angle increase affected the area of the solution flowing over the graphene resulting in the droplet width being shortened and a decrease in the induced voltage. The experimental results of this study provide optimal electrode placement and tilt angle for the best graphene energy harvest from the electrolyte.