2024年4月4日发(作者：)

层状双氢氧化物基复合材料的制备及其电化学性能的研究

The Construction of Layered Double Hydroxides-Based

Hybrid Materials for Electrochemical Application

Abstract

Two-dimensional (2D) materials have attracted increasing interest in electrochemical

energy storage andconversion. As typical 2D materials, layered double hydroxides (LDHs)

display large potential in this areadue to the facile adjustableof their composition, structure

and morphology. Various preparationstrategies, including in situ growth, electrodeposition

and layer-by-layer (LBL) assembly, have beendeveloped to directly modify electrodes by

using LDHs materials. Moreover, several composite materialsbased on LDHs and

conductive matrices have also been rationally designed and employed in supercapacitors,

batteries and electrocatalysis with largely enhanced performances.

This paper focus on the construction of LDHs-based composites and its application in

electrocatalytic hydrolysis and electrochemical energy storage carried out in a series of

trial and controllable synthesis of LDHs-based composites was realized by

the method of multi-step hydrothermal process and liquid phase self-assembly. As a result,

the electrochemical performance was enhanced.

The main contents of this paper are as following:

(1) Study on the construction of NiFe LDH@NiCo

2

O

4

composites

Herein, for the first time, we demonstrate NiFe-LDH ultrathin sheets with several

atomic layers grown on nickel cobalt oxide (NiCo

2

O

4

) nanowire arrays as an efficient

bifunctionalcatalyst toward both HER and OER reaction. Nickel (Ni) foam was used as the

electrode scaffold support because of its earth abundance and porous three-dimensional

2

O

4

, a typical OER electrocatalyst with high conductivity, was deposited on

the Ni foam in the form of rhombus/hexagonal plates interconnected into perpendicular

nanowire array morphology, efficientlyfacilitating electron transfer and electrolyte

permeation. The electrical conductivity in NiCo

2

O

4

has been believed to originate from the

III

层状双氢氧化物基复合材料的制备及其电化学性能的研究

presence of Ni

3+

and the electron transfer between Ni

2+

and Ni

3+

. Importantly, the surface

of NiCo

2

O

4

was a Ni-rich layer, which served as the seed for the following hierarchical

growth of NiFe-LDH, ensuring close contact and strong coupling at the interface.

(2) Study on the properties of electrocatalytic water splitting of NiFe LDH@NiCo

2

O

4

composites

Herein, the NiFe-LDH sheets were ultrathin of only several atomic layers, combined

with its strong coupling with NiCo

2

O

4

and the unique hierarchical structure, enabled the

hybrid electrode a remarkable overall water splitting performance of only 1.60 V to

achieve 10 mA cm

-2

current in single alkaline KOH eletrolyte.

Key words: Layered double hydroxides (LDHs)，Electrocatalysis, Overall water

splitting, Hydrogen evolution reaction, Oxygen evolution reaction，Heterostructure.

Written by: Zhiqiang Wang

Supervised by: Prof. Fengxia Geng

Prof. Xingwang Wang

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