Space-confined synthesis of multilayer Cu-N-doped graphene nanosheets for efficient oxygen electroreduction.

Cu-based carbon electrocatalysts for the oxygen reduction reaction are difficult to compare with the corresponding Fe- or Co-based electrocatalytic materials, owing to their insufficient catalytic activity and stability. Herein, as an impressive Cu-based electrocatalyst, a multilayer Cu-N-doped graphene sheet (Cu-N-GR) is directly synthesized by the thermal conversion of copper(ii) 2,2'-bipyridine in the confined space of lamellar montmorillonites. The open layered morphology of Cu-N-GR materials facilitated the exposure of more active centers and enhanced the flexibility and mobility of charge carriers. Combining the unique electronic properties of layered morphology and the synergistic effect of Cu and N, the obtained Cu-N-GR exhibits surprising results in terms of ORR catalytic activity, particularly in catalytic stability and methanol-tolerant properties in alkaline media.