Metal‐organic framework‐derived Fe/Cu‐substituted Co nanoparticles embedded in CNTs‐grafted carbon polyhedron for Zn‐air batteries

Abstract

Metal‐organic frameworks (MOFs) and MOF‐derived materials have attracted great attention as alternatives to noble‐metal based electrocatalysts owing to their intriguing structure properties, especially for high efficiency and stable oxygen reduction reaction (ORR). Herein, we employed a one‐pot reaction to make a multimetal (Fe, Co, Cu, and Zn) mixed zeolitic imidazolate framework (MM‐ZIF) via adopting a simple in situ redox reaction. Further pyrolysis of the target MM‐ZIF, a highly porous carbon polyhedron (FC‐C@NC) grafted with abundant carbon nanotubes was obtained, in which ultrasmall Co nanoparticles with partial lattice sites substituted by Fe and Cu were embedded. The obtained FC‐C@NC possessed large surface area, highly porous structure, widely‐spread metal active sites, and conductive carbon frameworks, contributing to outstanding ORR activity and long‐term stability. It displayed superior tolerance to methanol crossover and exceeded the commercial Pt/C catalyst and most previously reported non‐noble‐metal catalysts. Impressively, the as‐produced FC‐C@NC‐based zinc‐air battery afforded an open‐circuit potential of 1.466 V, a large specific capacity of 659.5 mAh/g, and a high gravimetric energy density of 784.3 Wh/kgZn, significantly outperforming the Pt/C‐based cathode.

Direct growth of ordered N‐doped carbon nanotube arrays on carbon fiber cloth as a free‐standing and binder‐free air electrode for flexible quasi‐solid‐state rechargeable Zn‐Air batteries

“…36,37 Specially, the content of pyridinic-N and F I G U R E 2 A, X-ray diffraction pattern of the CC-A-N@Co-NCNT and CC-A-N. B, Raman scattering spectra of CC-A-N@Co-NCNT, CC-A-N@Co, and CC-A-N, high-resolution elemental X-ray photoelectron spectras of Co-NCNT: (C) C 1s, (D) N 1s (E) Co 2p, and (F) O 1s graphitized-N accounts for approximately 97% of the total nitrogen in the structure, which are believed to be the active sites for ORR, thus favorable ORR activity is expected. 38 The high-resolution Co 2p 3/2 spectrum of Co-NCNT is shown in Figure 2E. Three peaks at 779.8, 781.8, and 785.7 eV can be identified as Co 3+ , Co 2+ , and satellite peak of Co 2+ , respectively.…”

MOFs‐Derived Carbon‐Based Metal Catalysts for Energy‐Related Electrocatalysis

“…They found that the metal ratios in these ternary alloys can be easily manipulated through regulating the dosage of precursors, which could affect the number of charger distribution between alloys and carbon shells at the same time. Guo and co-workers [137] utilized the simple redox reaction between Figure 9. a) Formation of FeCo alloy on carbon cage.…”

Defect Electrocatalysts and Alkaline Electrolyte Membranes in Solid‐State Zinc–Air Batteries: Recent Advances, Challenges, and Future Perspectives

“…Metal–organic frameworks (MOFs) with 3D ordered porous structure have been widely utilized to prepare ADMCs materials. [ 90,91 ] Atomically dispersed metal ions can be easily introduced in the metal nodes, organic ligands, or pores of MOFs because of their unique characteristics, including organic–inorganic hybrid nature, large surface area, well‐defined porosity, tunable chemical composition, and adjustable functionality. [ 92 ] Moreover, the uniformly distributed metal ions in pristine MOFs can be converted into ADMCs through simple heat treatment, forming the atomically dispersed metal sites anchored in MOF‐derived carbon materials.…”