Manipulating hydrogen and coordination bond chemistry for reversible zinc metal anodes

Zhongfu Yan; Miao He; Anjun Hu; Mengjiao Liu; Jiahao Chen; Jing Liu; Nian Chen; Liujun Cao; Baihai Li; Jianping Long

doi:10.1016/j.jcis.2023.06.196

Manipulating hydrogen and coordination bond chemistry for reversible zinc metal anodes

J Colloid Interface Sci. 2023 Nov 15;650(Pt A):257-265. doi: 10.1016/j.jcis.2023.06.196. Epub 2023 Jun 28.

Authors

Zhongfu Yan¹, Miao He², Anjun Hu³, Mengjiao Liu¹, Jiahao Chen¹, Jing Liu¹, Nian Chen⁴, Liujun Cao¹, Baihai Li⁵, Jianping Long⁶

Affiliations

¹ College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, 1#, Dongsanlu, Erxianqiao, Chengdu 610059, Sichuan, China.
² State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, China.
³ College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, 1#, Dongsanlu, Erxianqiao, Chengdu 610059, Sichuan, China; State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, China. Electronic address: anjunhu@feishu.uestc.cn.
⁴ The First Affiliated Hospital, Department of Medical Cosmetic, Hengyang Medical School, University of South China, Hengyang, Hunan 421001, China. Electronic address: chenniangood@126.com.
⁵ School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 610054, China.
⁶ College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, 1#, Dongsanlu, Erxianqiao, Chengdu 610059, Sichuan, China. Electronic address: longjianping@cdut.cn.

PMID: 37406566
DOI: 10.1016/j.jcis.2023.06.196

Abstract

Aqueous zinc ion hybrid capacitors (ZHCs) are promising as electrochemical energy storage devices due to their safety and cost-effectiveness. However, the practical application of aqueous ZHCs is impeded by zinc dendrite growth and side reactions induced by H₂O during long-term cycling. Herein, an organic small molecule, dimethyl sulfoxide (DMSO), is elaborately introduced into 2 M ZnSO₄ electrolyte to simultaneously overcome these challenges. As convincingly evidenced by experimental and theoretical results, the DMSO reconstructs the Zn[(H₂O)₆]²⁺ structure and original hydrogen bond networks at the molecular level. By forming coordination bonds with Zn²⁺ and hydrogen bonds with H₂O due to the stronger electron donating ability of oxygen in molecule, DMSO establishes a Zn²⁺ solvation shell structure that inhibits H₂O decomposition and dendrite growth. As a proof of concept, the implementation of this hybrid electrolyte in a Zn||Cu asymmetrical cell results in a high Coulombic efficiency (CE) of over 99.8% for 568 cycles at a current density of 2 mA cm^-2. Furthermore, the full cells using this hybrid electrolyte coupled with activated carbon (AC) cathode can operate for over 30,000 cycles. These results suggest that reconstructing the solvation structure and hydrogen bond networks guide the design of electrolytes for the development of high-performance aqueous ZHCs.

Keywords: Aqueous zinc ion hybrid capacitor; Electrolyte additive; Hydrogen evolution; Zn corrosion; Zn dendrite.