Synthesis and characterization of GO-PpPDA/Ni–Mn nanocomposite as a novel catalyst for methanol electrooxidation.

The graphene oxide-poly (p -phenylene diamine) (GP) composite is synthesized through in-situ polymerization of p -phenylene diamine on GO sheets and used as an efficient support material for electrodeposition of Ni and Mn. The resulting GP/Ni–Mn catalyst shows high catalytic activity, stability and durability for methanol electrooxidation. The surface area of GP composite is calculated to be about 28% and 36% higher than GO and PpPDA, respectively. In addition, combining Ni and Mn demonstrated some synergetic effect for methanol electrooxidation. The electrochemical active surface area of GP/Ni–Mn is about 1.625 cm2, which is much higher than GP/Ni and GP/Mn. GP/Ni–Mn nanocomposite presented 87.3% of the peak current after 5 h and almost 83.16% of the maximum current for 500 cycles. The excellent characteristics of this composite are attributed to high surface area, high electrochemical active surface area and fine distribution of metallic particles on the support material. • GO-PpPDA was synthesized via in-situ polymerization of pPDA and used to modify CPE. • Ni and Mn particles were deposited on the surface of modified CPE by chronoamperometry. • The electrochemical properties of different support materials were studied. • The nanocomposites used for electrooxidation of methanol in alkaline media. • The results showed the best performance of GO-PpPDA/Ni–Mn nanocomposite. [ABSTRACT FROM AUTHOR]