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Progress in Chemistry 2022, Vol. 34 Issue (12): 2686-2699 DOI: 10.7536/PC220405 Previous Articles   Next Articles

• CONTENTS •

The Application of CoFe Layered Double Hydroxide-Based Materials in Oxygen Evolution Reaction

Shixiang Xue, Pan Wu, Liang Zhao, Yanli Nan(), Wanying Lei()   

  1. College of Materials Science and Engineering, Xi’an University of Architecture and Technology,Xi’an 710055, China
  • Received: Revised: Online: Published:
  • Contact: Yanli Nan, Wanying Lei
  • Supported by:
    National Natural Science Foundation of China(51902243)
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Oxygen evolution reaction (OER) is a key process for green and sustainable energy storage and transfer technologies like electrocatalytic water splitting, rechargeable metal-air batteries, regenerative fuel cells, etc. Nevertheless, the high potential barrier and sluggish kinetic process limit its overall performance. Thus, designing and exploiting high-efficient, robust and noble-metal-free catalysts is one of the challenges in the field of new energy. CoFe layered double hydroxide (CoFe LDH) possesses broad prospects in OER due to the extraordinary features such as unique 2D layered structures, multiple and flexible chemical compositions, high dispersive metal cations, excellent stability and low cost. However, the poor conductivity and insufficient reactive sites hamper its industrial application. Beginning with the introduction of the structure of CoFe LDH and the elaboration of the proposed mechanisms for OER, the preparation of CoFe LDH and the current modification strategies for CoFe LDH to thoroughly boost its reactivity are summarized including intercalation and exfoliation, vacancy creation, hybridization, ions substitution and their derivatives. At last, the current challenges and future directions for LDH-based nanostructures in energy conversion and utilization are discussed.

Contents

1 Introduction

2 Fundamentals of LDHs for OER

2.1 Structure of LDHs

2.2 OER mechanisms of LDHs

3 Preparation of CoFe LDH

3.1 Precipitation and solvothermal methods

3.2 Electrodeposition

4 Modification strategies of CoFe LDH

4.1 Intercalation and exfoliation

4.2 Vacancy creation

4.3 Hybridization

4.4 Ions substitution

4.5 Derivatives

5 Conclusion and outlook

Table 1 Summary of the modification strategies for CoFe LDH-based electrocatalysts
Catalyst Current density/
mA·cm-2
Overpotential/
mV
Tafel slope/
mV·dec-1
Modification strategies ref
CoFe LDH/NF 10 260 47 Intercalation & Vacancy creation 62
HNO3 Exfoliated CoFe LDH(GC) 10 300 41 Intercalation & Vacancy creation 63
H2O-Plasma Exfoliated CoFe LDH(NF) 10 232 36 Exfoliation & Vacancy creation 64
Ar-Plasma Exfoliated CoFe LDH(NF) 10 237 38 Exfoliation & Vacancy creation 53
CoFe LDH(GC) 10 283 34 Intercalation and exfoliation &
Vacancy creation
65
Co8Fe1 LDH(NF) 10 262 42 Intercalation and exfoliation &
Vacancy creation
66
Se@CoFe LDH(NF) 50 251 47 Vacancy creation & Ions substitution 67
CeO2-x@CoFe LDH/NF 100 204 24 Vacancy creation & Hybridization 68
Rh-doped CoFe ZLDH/NF 100 245 - Vacancy creation & Ions substitution 69
N2-Plasma Exfoliated CoFe LDH(GC) 10 281 40 Vacancy creation & exfoliation 70
DH-CoFe LDH(GC) 10 280 40 Vacancy creation & exfoliation 71
CoO/CoFe LDH(CFP) 10 254 34 Hybridization 61
Co3O4/CoFe LDH(GC) 10 290 77 Hybridization 72
NiCo2O4@CoFe LDH/NF 20 273 108 Hybridization 73
CuO@CoFe LDH/CF 10 213 165 Hybridization 74
Cu@CoFe-LDH 10 240 45 Hybridization 75
CoP@CoFe LDH/NF 100 278 69.2 Hybridization 76
FeCo2S4@CoFe LDH/NF 100 259 68.9 Hybridization 77
Co0.4Fe0.6 LDH/g-CNx(GC) 10 280 29 Hybridization 78
CoFeV LDH/NF 10 242 57 Ions substitution 79
CoFeV LDH/CP 10 242 41.4 Ions substitution 80
CoFeMo LDH/NF 100 240 82.8 Ions substitution 81
Cr-CoFe LDH/NF 10 238 107 Ions substitution 82
CoFeCr LDH/NF 10 202 83 Ions substitution 83
Co0.4Fe0.6Se2/NF 10 217 41 Derivatives 84
Cr-CoFe LDH/NF 10 238 107 Ions substitution 82
CoFeCr LDH/NF 10 202 83 Ions substitution 83
Co0.4Fe0.6Se2/NF 10 217 41 Derivatives 84
CoFeP/NF 100 242 53 Derivatives 85
CoFeNx/NF 50 259 58 Derivatives 86
PO-CoFe LDH/NF 10 365 121 Derivatives 87
CoFeOOH@C(CFP) 10 254 33 Derivatives 88
CoFe LDH/TEG(GC) 10 301 52 Hybridization 89
Fig.1 Schematic illustration of the structure of LDHs[27]. Copyright 2021 The Royal Society of Chemistry
Fig.2Sche matic illustration of AEM and LOM[35]. Copyright 2018 American Chemical Society
Fig.3 (a) Schematic showing the preparation of CoFe LDH nanosheets by water-plasma-enabled plasma exfoliation[64]. Copyright 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. (b) Schematic representation of CoFe LDH by Ar plasma exfoliation method, (c) Height profiles of the samples by AFM images and (d) LSV curves of CoFe LDH and CoFe LDH-Ar[53]. Copyright 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Fig. 4 (a) EPR curves and (b) Tauc plots of CoFe LDH and Se@CoFe LDH[67]. Copyright 2021 American Chemical Society. (c) Schematic illustrating the synthesis method of the Rh-doped CoFe LDH@NF[69]. Copyright 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Fig. 5 (a-b) AFM images of the N2-CoFe LDH nanosheets, The XPS O 1s spectrum of (b) CoFe LDH and (c) CoFe LDH-N2[70]. Copyright 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Fig. 6 (a) Schematic showing the preparation of CoO/CoFe LDH composites, (b) Schematic illustration of the electron transfer at the interface of the CoO/CoFe LDH hybrid, (c) LSV curves of the prepared catalysts[61]. Copyright 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Fig. 7 SEM images of (a) CuO and (b) Cu@CoFe LDH core-shell nanomaterials, (c) Polarization curves and (d) charging current density plots with different scan rates of CuO and Cu@CoFe LDH core-shell nanohybrid electrocatalysts[74]. Copyright 2020 American Chemical Society
Fig. 8 (a) Schematic showing the synthesis procedure of CrCoFe LDH/NF, (b) DFT calculations of the free energy of the intermediates, (c) LSV curves of the as-prepared catalysts[82]. Copyright 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Fig. 9 (a) Schematic illustration of the preparation of CoFeNx/NF, (b-c) SEM images of CoFeNx /NF[86]. Copyright 2020 American Chemical Society
Fig. 10 (a) Schematic diagram of the fabrication of Co0.8Fe0.2OOH@C, (b) Polarization curves and (c) Tafel slopes of the prepared catalysts[88]. Copyright 2020 Wiley-VCH GmbH
Table 2 Advantages and disadvantages of various modification methods
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