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.

Random Occupation of Multimetal Sites in Transition Metal‐Organic Frameworks for Boosting the Oxygen Evolution Reaction

“…[3] However, their potential in widespread practical applications may be limited by the high cost and limited availability. [4] Typically, the OER occurs on the surface metal sites (M) during the alkaline OER process for the transition metal-based heterogeneous catalysis. The OER mechanism includes the formation of MÀ OH (the hydroxide anions absorbed on the metal active site), the transformation of MÀ OH to MÀ O and a further transformation of MÀ O to MOOH; finally, the oxygen is released, and catalysts come back to the initial state of M. [5] The binding energy of oxygen intermediates OH*, O* and OOH* (* represents the adsorbed state) on the catalyst surface has been considered the main governing parameter.…”

“…Ruthenium oxides (RuO 2 ) and iridium oxides (IrO 2 ) have been explored as commercial electrocatalysts for OER, especially in acidic environment, but also in alkaline [3] . However, their potential in widespread practical applications may be limited by the high cost and limited availability [4] . Typically, the OER occurs on the surface metal sites (M) during the alkaline OER process for the transition metal‐based heterogeneous catalysis.…”

Fabrication of FeOOH/BiOCl Nanocomposites with Enhanced Visible Light Photocatalytic Activity

“…With the developed industrialization, more and more environment problems and energy problems have threatened our daily life . In 1972, the TiO 2 was used for photocatalytic splitting of water .…”

A Photodynamic System based on Endogenous Bioluminescence for in vitro Anticancer Studies

“…Biomaterials for diagnosis or therapy have been investigated for decades . Nowadays, the photodynamic therapy (PDT) has been receiving great attention in cancer treatments .…”