Thinly-walled NiFe2O4 nanotubes derived from Ni, Fe, N-codoped carbon nanofibers toward oxygen evolution reaction

NiFe 2 O 4 has emerged as an efficient oxygen evolution reaction (OER) electrocatalyst, with outstanding stability in alkaline media and excellent redox properties. In order to further improve the catalytic performance, thinly-walled NiFe 2 O 4 nanotubes (NiFe 2 O 4 -NTs), efficiently derivable from Ni, Fe, N-codoped carbon nanofibers, were innovatively synthesized through a sequential route combing hydrothermal, electrospinning, and high-temperature sintering in this work. The NiFe 2 O 4 -NTs possess large diameter of around 120 nm and their thickness of the tube wall is only about 10 nm. The surface properties of NiFe 2 O 4 can be adjusted by forming the Ni-N/Fe-N bonds. Excitingly, largely exposed active surface area and boosted catalytic reaction kinetics toward oxygen evolution reaction are realized. The required overpotential to deliver 10 mA cm −2 is only 331 mV, accompanied with favorable Tafel slope of only 51.8 mV dec −1 , small charge transfer resistance, and superior reaction stability.