Engineering hybrid between nickel oxide and nickel cobaltate to achieve exceptionally high activity for oxygen reduction reaction

•Porous NiO/NiCo2O4 nanotubes were prepared by coaxial electrospinning-assisted method.•They exhibit significantly enhanced electrocatalytic activity for ORR.•The good ORR performance may be attributed to their unique microstructures.

The porous NiO/NiCo2O4 nanotubes are prepared via a coaxial electrospinning technique followed by an annealing treatment. The resultant NiO/NiCo2O4 hybrid is developed as a highly efficient electrocatalyst, which exhibits significantly enhanced electrocatalytic activity, long-term operation stability, and tolerance to crossover effect compared to NiO nanofibers, NiCo2O4 nanofibers and commercial Pt(20%)/C for oxygen reduction reactions (ORR) in alkaline environment. The excellent electrocatalytic performance may be attributed to the unique microstructures of the porous NiO/NiCo2O4 nanotubes, such as heterogeneous hybrid structure, open porous tubular structure, and the well dispersity of the two components. Moreover, the promising and straightforward coaxial electrospinning proves itself to be an efficient pathway for the preparation of nanomaterials with tubular architectures and it can be used for large-scale production of catalysts in fuel cells.

Graphical abstractThe porous NiO/NiCo2O4 nanotubes were prepared by a facile route, which exhibit significantly enhanced electrocatalytic activity, long-term operation stability, and tolerance to crossover effect as a highly efficient electrocatalyst for ORR in alkaline environment.Figure optionsDownload full-size imageDownload as PowerPoint slide