Oxygen-defect-rich 3D porous cobalt-gallium layered double hydroxide for high-performance supercapacitor application

Heng Zhang; Youcun Bai; Hang Chen; Jinggao Wu; Chang Ming Li; Xintai Su; Lijuan Zhang

doi:10.1016/j.jcis.2021.10.109

Oxygen-defect-rich 3D porous cobalt-gallium layered double hydroxide for high-performance supercapacitor application

J Colloid Interface Sci. 2022 Feb 15;608(Pt 2):1837-1845. doi: 10.1016/j.jcis.2021.10.109. Epub 2021 Oct 20.

Authors

Heng Zhang¹, Youcun Bai², Hang Chen³, Jinggao Wu⁴, Chang Ming Li⁵, Xintai Su⁶, Lijuan Zhang⁷

Affiliations

¹ Institute for Clean Energy & Advanced Materials, Faculty of Materials and Energy, Southwest University, Chongqing 400715, PR China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; Ministry Key Laboratory of Oil and Gas Fine Chemicals, College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, China.
² School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China.
³ Ministry Key Laboratory of Oil and Gas Fine Chemicals, College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, China.
⁴ Key Laboratory of Rare Earth Optoelectronic Materials & Devices, College of Chemistry and Materials Engineering, Huaihua University, Huaihua 418000, China.
⁵ Institute for Clean Energy & Advanced Materials, Faculty of Materials and Energy, Southwest University, Chongqing 400715, PR China.
⁶ The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China.
⁷ The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China. Electronic address: zhanglj112@163.com.

PMID: 34742092
DOI: 10.1016/j.jcis.2021.10.109

Abstract

In this work, oxygen-defect-rich, three-dimensional (3D) cobalt-gallium layered double hydroxides (Co_0.50-Ga_0.50-LDH) assembled by porous and ultrathin nanosheets are prepared by a simple one-step strategy. Briefly, an aqueous solution containing Co²⁺ and Ga³⁺ is quickly pouring into the aqueous solution of hexamethylenetetramine, the state-of-the-art LDH was obtained followed by a mild and fast hydrothermal reaction. This mild and rapid synthesis strategy introduces a large number of pores into the ultrathin LDH nanosheets, resulting in a high concentration of oxygen vacancies in the Co_0.50-Ga_0.50-LDH, and the concentration of oxygen vacancies can be arbitrarily modulated, which has been corroborated by X-ray photoelectron spectroscopy and electron spin resonance measurements. The synergistic effect of the oxygen vacancy and the introduced Ga ions in the LDH nanosheets enhances the adsorption of the LDH nanosheets on OH^-, endowing Co_0.50-Ga_0.50-LDH with outstanding performance for the supercapacitor application. Co_0.50-Ga_0.50-LDH offers a high specific capacity (0.62C·cm^-2) at 10 mV·s^-1 and extraordinary cycling stability. An aqueous asymmetric supercapacitor (ASC) constructed with Co_0.50-Ga_0.50-LDH and activated carbon (AC) materials exhibits high energy density and a long lifespan. This result encourages the wide application of porous ultrathin LDH nanosheets in energy storage, catalysis and light response.

Keywords: Asymmetric supercapacitors; Layered double hydroxide; Porous ultrathin nanosheets; Vacancy modulation.