The design of new electrocatalysts based on transition metals for direct alcohol fuel cells can lead to the wide application of these renewable energy sources by reducing costs and improving stability. Here, we report a hydrothermal method to modify graphene oxide (GO) by the addition of multiwalled carbon nanotubes (MWCNTs) to prepare reduced GO (rGO)-MWCNT as a support material for direct methanol fuel cells. Oxid composites based on Mn, Co, and Cu are synthesized and placed on the surface of the support material through a hydrothermal method. Structural and textural characteristics of bimetallic and trimetallic nanohybrids are examined. Modified carbon paste electrodes are used to study the electrochemical performance of nanohybrids toward methanol electrooxidation in an alkaline medium. The modified support material shows higher surface area and porosity compared to GO, which increased the amount of loading without agglomeration of metallic particles. The current density obtained by rGO-MWCNT/Mn-Co-Cu is higher compared to bimetallic catalysts with the same support material, which confirms the synergistic effect of using these metals together. This nanohybrid preserves 91.40% and 83.01% of the initial current density after 500 and 1000 cycles of cyclic voltammetry, respectively. The high stability and durability of rGO-MWCNT/Mn-Co-Cu confirm that this transition metal-based nanohybrid can be effectively used as an electrocatalyst for methanol electrooxidation in an alkaline medium.
