Effects of catalyst aging on the growth morphology and oxygen reduction activity of nitrogen-doped carbon nanotubes

•Effect of catalyst aging time on the behavior of nitrogen-doped carbon nanotubes•Changes of morphology, surface composition and electrocatalytic properties of N-CNTs induced by aging of synthesis catalyst•Electrocatalytic properties towards Oxygen Reduction Reaction of N-CNTs. Effects of aging of catalyst used in the synthesis.

This work reports some effects that aging time of the used catalyst (Fe/MgO) has on the produced N-doped carbon nanotubes. In particular, the catalyst age affects the synthesized nanomaterials with respect to morphology, surface composition and electrocatalytic behavior towards the electrochemical oxygen reduction.