Trimetallic Nanoparticles Encapsulated into Bamboo‐Like N‐Doped Carbon Nanotubes as a Robust Catalyst for Efficient Oxygen Evolution Electrocatalysis

Abstract

High-efficiency oxygen evolution reaction (OER) electrocatalysts based on transition metal materials are one of the most promising alternatives, but their activity and durability are still far from desirable. Here, we report trimetallic N-doped carbon nanotubes with rapid electron transport and rapid diffusion of the electrolyte that can significantly enhance the OER. The introduction of a third metal can adjust the electronic structure, thereby causing favorable intermediate adsorption on the catalysts. The optimized catalyst CoFeNi@CNTs exhibits a low overpotential of 287 mV at 10 mA cm À 2 and a small Tafel slope of 32 mV dec À 1 , which are obviously superior to the precious catalyst IrO 2 and most previously reported catalysts. The CoFeNi@CNTs also exhibit excellent OER stability with small current density decay after 12 h. The outstanding OER activity is ascribed to the unique carbon nanotube structure and strong synergy between three metals.

Zeolitic Imidazolate Framework-Derived Co-Fe@NC for Rechargeable Hybrid Sodium–Air Battery with a Low Voltage Gap and Long Cycle Life

“…For the Co-Fe@NC sample, an additional peak of Co 3 Fe 7 (PDF # 48-1817) was observed. It is suspected that Fe/Co precursors in the FeCoZn-ZIFs were reduced to metallic Co 3 Fe 7 by its organic skeleton and metallic iron combined with the surrounding carbon and nitrogen formed Fe 3 C and FeN 0.0324 under a high temperature . Raman spectra (Figure c) of the electrocatalyst presents two peaks centered at ∼1330 cm –1 (D band) and ∼1583 cm –1 (G band).…”

Phosphorus modification of cobalt–iron nanoparticles embedded in a nitrogen-doped carbon network for oxygen reduction reaction

“…Such NC have been shown to exhibit a higher activity compared to common CNTs. [38][39][40] In addition, the thinner wall can ease penetration of electrons from the metal cores to the carbon surface. These features could be responsible for the observed superior ORR performance.…”

Single‐Source‐Precursor Derived Transition Metal Alloys Embedded in Nitrogen‐Doped Porous Carbons as Efficient Oxygen Evolution Electrocatalysts

“…FeNi/NC [28] 1 M KOH 0.566 mg cm À 2 1.58 V FeNi/NCNT [28] 1 M KOH 0.566 mg cm À 2 1.62 V FeNi@N-CNT/NCSs [19] 1 M KOH > 0.25 mg cm À 2 1.54 V FeNi@NC-NG [29] 1 M KOH 0.5 mg cm À 2 1.50 V FeNiNCFs [26] 1 M KOH 0.255 mg cm À 2 1.547 V FeNi/N-CPCF [24b] 0.1 M KOH 0.60 mg cm À 2 1.58 V FeNi/NC [30] 1 M KOH 0.337 mg cm À 2 1.528 V fd-FeNi/C [31] 1 M KOH 0.382 mg cm À 2 1.531 V FeNi@NCNT-CP [32] 0.1 M KOH 0.40 mg cm À 2 1.59 V FeNiNC-550-3 [33] 0.1 M KOH 0.57 mg cm À 2 1.57 V FeNiP/NPCS [34] 1 M KOH 0.25 mg cm À 2 1.548 V FeNi@CNTs [35] 1 M KOH 0.354 mg cm À 2 1.549 V FeNi@NC-900 this work 1 M KOH 0.225 mg cm À 2 1.54 V ChemPlusChem alloy@NC. It is assumed that the alloy nanoparticles encapsulated by the nitrogen doped carbon accelerate the electron transfer rate during the reaction process.…”