Plasma synthesis of Pt nanoparticles on 3D reduced graphene oxide-carbon nanotubes nanocomposites towards methanol oxidation reaction

The reduced graphene oxide and carbon nanotubes supported Pt nanocomposites (Pt/GNTs) with high catalytic activity for methanol oxidation reaction (MOR) have been prepared via tuning the mass ratio of graphene oxide (GO) and multi-wall carbon nanotubes (MWCNTs). The H2 plasma discharge technique was employed to irradiate catalyst precursor for reducing Pt ions and GO because of high energy electrons and activated ions in plasma. Compared with other as-prepared composites and commercial Pt/C, Pt/GNTs (GO:CNT = 1:2) exhibited higher electrochemical performances, which is attributed to the synergic effects of graphene and CNTs. The forward current density of Pt/GNTs (GO:CNT = 1:2, 691.1 mA mg−1) is much larger than that of commercial Pt/C (368.2 mA mg−1) for MOR. After 3600 s chronoamperometry (CA) test, the current density also remains 97.9 mA mg−1, which is 2.2 times larger than commercial Pt/C (44.1 mA mg−1). In addition, the dispersion of Pt nanoparticles (NPs) on GO and CNTs is much related to the mass ratio of them owing to the difference of oxygen-containing functional groups. Meanwhile, the addition of GO seems to promote the anti-poisoning ability of catalysts due to the hydroxyl (OH) oxidation for intermediate carbonaceous species. This work is meaningful to prepare other Pt based catalysts for MOR, and the as-prepared Pt/GNTs (GO:CNT = 1:2) is a promising novel metal catalyst for the application to new-style direct methanol fuel cells (DMFCs).