Supramolecular Nanofiber Templated Metal‐embedded Nitrogen‐doped Carbon Nanotubes for Efficient Electrocatalysis of Oxygen Evolution Reaction

Abstract

Nowadays, there still exists big challenges to synthesize active and inexpensive electrocatalysts for oxygen evolution reaction. In this work, we propose a new method by using melamine‐uric acid (MAUA) supramolecular nanofibers as precursor to fabricate metal‐embedded nitrogen‐doped carbon nanotube materials (MM′@NCNTs, M, M′ = Fe, Co, Ni). The samples exhibit superior and stable catalytic performance for oxygen evolution reaction (OER) in alkaline medium. In all the electrocatalysts, FeNi@NCNT shows the best electrocatalytic activity with the overpotential is only 402 mV (vs. RHE) at 10 mA·cm–2, which shows better performance than both Fe@NCNT and Ni@NCNT. The smaller Tafel slope value, with the value of 68 mV·dec–1, indicates the superior OER activity of FeNi@NCNT. These results reveal a synergistic effect between Fe, Co, and Ni, which could produce a favorable coordination environment that enhance the activity for oxygen evolution reaction.