Design and Development of Methanol Sensing MEMS Sensor for DMFC Technology

Abstract

The sensors can be developed based on ampherometric principle using Direct Methanol Fuel Cell (DMFC) technology. The synthesis of cost effective electrocatalyst materials for improved oxygen reduction reaction (ORR) and preparing electrodes by using suitable methods to reduce the cost of the sensing electrode is the major objective of the present work. Pt-Sn alloy exhibits high sensitivity in ORR among other Pt alloys and hence will be used as the ORR catalysts. For various concentration of methanol at different temperature, the current density of the chemically synthesised and characterized Pt-Sn/C was analysed. The accuracy will be determined by the detection of electric current or changes in electric current to design the sensor. To analyse the sensor accuracy, we have used passive mode design protocol in COMSOL Multiphysics. From the constructed cell of 1.0 cm cell area, we can optimize the overall power density and hence the sensitivity of the sensor by the modification of the cell parameters and interfacing it with Darcy’s law of fluidic flow through porous electrode medium. The micro electro mechanical systems (MEMS) technology was used for the design and fabrication of sensor with the electrochemical inputs from a standard DMFC single cell arrangement. The cell structure has been fabricated using a 3D printing technology and the output of the cell was optimized for ampherometric detection. The sensor with microfludic interconnects were fabricated by MEMS technology. The sensor response characteristics were studied and will be presented.