Ni-MOF/rGO Composites for Methanol Oxidation in Direct Methanol Fuel Cell

Abstract

The substantial inflation in energy consumption has leaded the research activities in development of renewable energy fuel cell. DMFC is an extraordinarily promising energy source because of its easy handling and fuel processing. Direct methanol fuel cells convert chemical energy into electrical energy through methanol oxidation. Research in the preparation of non noble metal based catalyst for methanol oxidation has been accelerated. During the last decade the electro oxidation of methanol at MOF and their composites with rGO has attracted appreciable attention in DMFC. Here we report the electrochemical activity of Ni-MOF and its composites with rGO for methanol oxidation. The prepared Ni based MOFs and their composites with rGO were synthesized via hydrothermal method. The prepared catalytic material was characterized through scanning electron microscopy, electron dispersive spectroscopy, X-ray diffraction and FTIR for testing their structural and morphological changes. The electro catalytic activity and stability of prepared catalyst was investigated for methanol oxidation through cyclic voltammetry, electron impedance spectroscopy and chronoamperometry in an alkaline medium. The electrochemical parameters were calculated by glassy carbon electrode modified with Ni MOF and their composites and illustrate the effect of rGO on the oxidation of methanol. Among all the composites 5wt% rGO/ Ni MOF illustrate an excellent peak current density 275.85mA/cm2 at lower scan rate 50mV/s and stability up to 60%. The increased electrochemical activity and considerable stability is associated with the combined effect of rGO with MOFs for methanol oxidation.