The potential of metal oxide-based nanocatalysts and multi-walled carbon nanotubes (MWCNTs) for the methanol and ethanol electrooxidation process is studied in the attempt of introducing cheap and stable nanocatalysts for use in the alcohol oxidation process. In this regard MnO2-NiO (MN), and MnO2-NiO-MWCNT (MNM) are synthesized and characterized in terms of structure and morphology. The electrocatalytic activity of these materials is evaluated by electrochemical tests. MnO2-NiO-MWCNT show 90% cyclic stability after 1000 consecutive cycles in methanol oxidation reaction (MOR) and 86% in ethanol oxidation reaction (EOR) and maximum current densities of 262 and 148 μA/cm2 in methanol and ethanol electrooxidation, in scan rate of 10 mV/s respectively. Also, the onset potential of MnO2-NiO-MWCNT is lower than MnO 2 -NiO, indicating superior kinetics and facile oxidation of methanol due to the synergistic effect of adding MWCNTs to the structure of MnO2-NiO nanocatalyst. From these results, MnO2-NiO-MWCNT can be an attractive and inexpensive option for use in MOR and EOR process for application in alcohol fuel cells.

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This study provides the methanol oxidation capability of two nanocatalysts, CeO2-NiO (CN) and CeO2-NiO-rGO (CNR), synthesized by a cost-effective hydrothermal method. The synergistic effect of compositing CeO2-NiO with reduced graphene oxide was evaluated. These synergic effect makes a good electrochemical active surface area and suitable electrical conductivity for catalyst. In addition, rGO with good electrical conductivity revealed considerable improvement in the methanol oxidation reaction (MOR) performance of the catalyst. The cyclic stability measurements of CeO2-NiO-rGO showed a high retention ability of 96% in 500 consecutive CV cycles, while the stability of CeO2-NiO in the same number of cycles is about 93%. The complementary methanol oxidation process results indicated an oxidation current density up to 49.5 and 68.5 mA/cm2 for CN and CNR at a scan rate of 20 mV/s, respectively. The proposed catalyst can be considered as an attractive, stable, and inexpensive candidate in the field of methanol oxidation to use in methanol fuel cells.