Engineering active sites on hierarchical ZnNi layered double hydroxide architectures with rich Zn vacancies boosting battery-type supercapacitor performances.

Impact Factor:

6.901

DOI number:

10.1016/j.electacta.2021.137932

Journal:

Electrochim. Acta

Key Words:

Hierarchical architectures, Zn vacancies, Electron conductivity, Active sites, Supercapacitor

Abstract:

Designing metal-cation defects with desired architectures is a big challenge for boosting electrochemical performances. Herein, we report ultrathin ZnNi layered double hydroxide (LDH) nanosheets with rich Zn vacancies (V-Zn) uniformly anchored on CuO nanowire skeletons for high performance capacitive electrode via a zeolitic imidazolate frameworks-8 derived approach. The optimized V-Zn-defect electrode displays high area capacity of 3967 mF cm(-2) at a current density of 2.0 mA cm(-2). Moreover, an all solid-state hybrid supercapacitor constructed with the V-Zn-defect sample and activated carbon delivers a maximum energy density of 1.03 mWh cm(-3) at a power density of 9.3 mW cm(-3). Mechanism studies indicate that V-Zn regulates the electronic structure of ZnNi LDH nanosheets for electron conductivity and surface Faradaic reactions. The work may disclose the role of metal-cation defects in affecting the electrochemical activity at atomic level for developing high performance supercapacitors.

Co-author:

Jiawei Xue, Lan Yang

First Author:

Haoyang Wu, Xiaoqing Zhang

Correspondence Author:

Hui Zhang, Shikuo Li

Document Type:

SCI

Volume:

374

Page Number:

137932

Translation or Not:

no

Date of Publication:

2021-02-10

Links to published journals:

https://www.sciencedirect.com/science/article/pii/S001346862100222X