Influence of Pd₁Pt_x alloy NPs on graphene aerogel/nickel foam as binder-free anodic electrode for electrocatalytic ethanol oxidation reaction

Highly active and stable electrocatalysts for ethanol oxidation reaction (EOR) are very important for applications in fuel cells. Even though huge efforts have been devoted to enhancing their catalytic activity, preparation of open-structure electrodes by a green and binder-free method remains a challenge. It is obvious in graphene aerogel (GA) based materials due to the destruction of the original GA structure by traditional fabrication methods. In this report, Pd₁Pt_x alloy NPs/GA/nickel foam electrodes (Pd₁Pt_x/GA/NF) were prepared by a green, simple and binder-free one-step method. The results show that the mean particle size and distribution of Pd₁Pt_x alloy NPs and the Pd₁Pt_x loading ratios (at%; x = 2.92, 1.31, 1.03) on the electrodes are strongly dependent on the initial concentration of PtCl₆²⁻ ions in the synthesis solution. The Pd₁Pt_x/GA/NF electrodes were evaluated for EOR. The Pd₁Pt_1.03/GA/NF electrode exhibits high activity and stability in EOR under a long operation (1000 cycles), which are attributed to the synergistic effect of the bimetallic Pd₁Pt_x alloy NPs on the electrode. This study introduced a binder-free, current-collector-free electrode preparation method which may provide new opportunities to develop high-performance electrodes for energy generation and storage technologies.