Solid waste-derived γ-Al2O3 nanowires supporting α-Fe2O3 as an efficient anodic direct methanol fuel cell electrocatalyst

The hybrid nanowires γ-Al2O3/AlOOH (Al) electrocatalyst synthesized via the Bayer route from a solid waste were loaded with α-Fe2O3 (12%) exploiting a deposition-hydrothermal approach, then characterized using XRD, FTIR, TEM-SAED, XPS and N2 porosimetry techniques. An efficient methanol oxidation activity of the 12% Fe/Al electrode displayed a current density of 25 mA cm-2 in an acid environment exceeded the individual electrodes Al and α-Fe2O3 by 3 and 8 times, respectively. It has been established that the activity, kinetics, and stability of the 12 % α-Fe2O3/Al electrode exceeded that of the individual analogues and was rather controlled by the diffusion mechanism. This was attributed to the increasing surface area of the composite electrode, its pore volume, pore apertures and decreased particle diameter. It was apparent that γ-Al2O3/AlOOH sites were responsible for dehydration until approaching CO species that were mostly being oxidized to CO2 on α-Fe2O3, as evidenced by the CO stripping results.