Electrochemical investigation of Metal- Malonyldihydrazide complexes for Direct Methanol Fuel Cell Application

Abstract

Developing active and high efficient electro catalyst for the methanol oxidation is very important for the large scale commercialization of Direct Methanol Fuel Cell (DMFC). Here we report the metal-complex based catalyst providing a large potentiality to generate a new function compared to metal alloy catalysts. We formulated Iron malonyl dihydrazide, Copper malonyl dihydrazide, and Cobalt malonyl dihydrazide complexes by simple chemical synthesis. The prepared catalysts were characterized by the IR studies to confirm the metal-complex formation. The prepared catalysts were coated on the stainless steel mesh substrate with the incorporation of carbon powder. The modified electrodes were investigated for the methanol oxidation in 0.5M sulphuric acid medium through Cyclic Voltammetry. The results indicate Fe- malonyldihydrazide (abbreviated as Fe-MDH) complex shows efficient electro oxidation of methanol with better stability during long term potential cycling. The Fe-MDH modified electrode oxidizes the methanol at around 0.6V. The studies were optimized by varying the Fe-MDH ratio with carbon powder, catalyst drying temperature and concentration of the acidic medium. The modified Fe-MDH electrode was characterized using BET surface analysis, XRD, SEM analysis. Fuel cell performance was carried out which shows current density about 77mA/cm2.