Enhancement of Electrochemical Reaction Rate on Galvanic Arrays in Contact with Condensed Water Molecules

Abstract

Galvanic current flows when water bridges over the adjacent arrays of Au and Al intercalated with each other with micro/nano gap in a microgalvanic cell. This cell is capable of sensing small water droplet and condensed water molecules and enables it to apply in the detection of dew condensation at an early stage. Enhancing galvanic current, i.e. electrochemical reaction rate of this system, improves its sensitivity as a sensor. This study clarified that cathodic reaction in the galvanic action between the Au and Al arrays in contact with condensed water molecules under the atmospheric condition should be reduction of oxygen gas on the Au array. Galvanic current could be enhanced by coating Pt on Au electrode, by enhancing the oxygen reduction reaction, increasing the sensitivity of microgalvanic cell as a sensor.