Gram-scale production of in-situ generated iron carbide nanoparticles encapsulated via nitrogen and phosphorous co-doped bamboo-like carbon nanotubes for oxygen evolution reaction

•The iron-based electrocatalyst is prepared by a novel in-situ single-step carbonization approach.•The composites obtained at 800 0C shows remarkable OER performance in the alkaline solution.•Electrocatalytic activity exceeds the benchmark RuO2 electrocatalyst.•Co-doped carbon nanotubes with nitrogen and phosphorus can improve the electronic structure to increase electrocatalytic performance.•The enhanced performance resulted from the multicomponent synergetic effect.