Morphology-dependent electrocatalytic performance of Fe2(MoO4)3 for electro-oxidation of methanol in alkaline medium

Electrochemically synthesized nanosphere, nanorod and nanotube Fe2(MoO4)3 at optimized temperature and current density are characterized with XRD, SEM, TEM, XPS. Crystal lattices of the three types Fe2(MoO4)3 detected by HRTEM are well matched with the simulation analysis results from Materials Studio 6.0 based on the inorganic crystal structure database (ICSD) data and the modified XRD lattice parameters. The ratios of Fe/Mo on the surface resulted from XPS analysis are 1.47, 1.63 and 2.22 respectively for nanosphere, nanorod and nanotube. The mixture of Fe2(MoO4)3 with polytetrafluoroethylene dispersion are coated on glass carbon substrate as electrode for electrocatalytic performance test by cyclic voltammetries in 0.1 mol/L KOH and 1 mol/L methanol electrolyte. Methanol oxidation peak current density of the Nanotube- Fe2(MoO4)3/GCEs electrode is 3.27 mA/cm2 higher than 2.8 mA/cm2 of platinum foil electrode, which shows enhanced catalytic activity of Nanotube-Fe2(MoO4)3/GCEs. The cyclic stability in terms of peak current retention are 91%, 92% and 88% respectively for Nanosphere-Fe2(MoO4)3/GCE, Nanorod-Fe2(MoO4)3/GCE and Nanotube-Fe2(MoO4)3/GCE electrode after 220 cycles. It is concluded that nanosized Fe2(MoO4)3 could be promising alternative non-noble electro-catalysts for electro-oxidation of methanol in alkaline medium.