fig4

Figure 4. (A) Illustration of the fabrication route of NiFe-btz/NF-OH electrode; (B) and (C) SEM images for NiFe-btz/NF-OH electrode; (D) and (E) Electrocatalytic properties of NiFe-btz/NF-OH and other samples for OER. (A)-(E) were reproduced with permission^[80]. Copyright 2022, Wiley-VCH; (F) Schematic illustration for constructing hierarchical porous MOF/LDH heteronanotube array electrode on CC substrate with prolonged reaction times. (a) SEM images of CoNiFe-LDH template, (b-e) SEM images of cMOF and cMOF/LDH obtained from 12, 24, 48, and 72 h reactions; (G) LSV curves of CoNiFe-LDH template and cMOF/LDH heteronanotube arrays; (H) Comparison for overpotentials of CoNiFe-LDH and cMOF/LDH heteronanotube arrays; (F)-(H) were reproduced with permission^[45]. Copyright 2021, Wiley-VCH. btz: 1,4-bis(4H-1,2,4-triazol4-yl)benzene; SEM: scanning electron microscope; OER: oxygen evolution reaction; cMOF: conductive metal-organic framework; LDH: layered double hydroxide; CC: carbon cloth; LSV: linear sweep voltammetry.