{"title":"Charge polarity inversion and zincophilicity improvement for chitosan separator towards durable aqueous zinc-ion batteries","authors":"","doi":"10.1016/j.jechem.2024.09.036","DOIUrl":null,"url":null,"abstract":"<div><div>Aqueous zinc-ion batteries encounter enormous challenges such as Zn dendrites and parasitic reactions. Separator modification is a highly effective strategy to address these issues. With the advantages of low cost, nontoxicity, biodegradability, good film-forming ability, superior hydrophilicity, and rich functional groups, chitosan is an ideal matrix for constructing separators. However, the presence of positive charges within chitosan in weakly acidic electrolytes is unfavorable for dendrite inhibition. Herein, Schiff base reaction is introduced to modify chitosan matrix, transforming its charge polarity from positive to negative. Additionally, NbN with excellent zincophilicity is coated onto chitosan matrix, forming a Janus separator with low thickness of 19 μm and considerably improved mechanical properties. The resultant separator can promote the transport of Zn<sup>2+</sup> ions while triggering a repulsive shielding effect against anions, therefore dramatically enhancing Zn<sup>2+</sup> ion transfer number from 0.28 to 0.49. This separator can also facilitate desolvation process, improve exchange current density, restrict two-dimensional Zn<sup>2+</sup> ion diffusion, and enhance electrochemical kinetics, contributing to significantly inhibited dendrite growth, by-product formation, and hydrogen evolution. Consequently, stable and reversible Zn stripping/plating process is enabled for over 2500 h at 2 mA cm<sup>−2</sup> and 2 mAh cm<sup>−2</sup>. And great rate capability and excellent cyclability can be achieved for full batteries even under harsh conditions. This work provides new insights into separator design for Zn-based batteries.</div></div>","PeriodicalId":15728,"journal":{"name":"Journal of Energy Chemistry","volume":null,"pages":null},"PeriodicalIF":13.1000,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Energy Chemistry","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2095495624006600","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Energy","Score":null,"Total":0}
引用次数: 0
Abstract
Aqueous zinc-ion batteries encounter enormous challenges such as Zn dendrites and parasitic reactions. Separator modification is a highly effective strategy to address these issues. With the advantages of low cost, nontoxicity, biodegradability, good film-forming ability, superior hydrophilicity, and rich functional groups, chitosan is an ideal matrix for constructing separators. However, the presence of positive charges within chitosan in weakly acidic electrolytes is unfavorable for dendrite inhibition. Herein, Schiff base reaction is introduced to modify chitosan matrix, transforming its charge polarity from positive to negative. Additionally, NbN with excellent zincophilicity is coated onto chitosan matrix, forming a Janus separator with low thickness of 19 μm and considerably improved mechanical properties. The resultant separator can promote the transport of Zn2+ ions while triggering a repulsive shielding effect against anions, therefore dramatically enhancing Zn2+ ion transfer number from 0.28 to 0.49. This separator can also facilitate desolvation process, improve exchange current density, restrict two-dimensional Zn2+ ion diffusion, and enhance electrochemical kinetics, contributing to significantly inhibited dendrite growth, by-product formation, and hydrogen evolution. Consequently, stable and reversible Zn stripping/plating process is enabled for over 2500 h at 2 mA cm−2 and 2 mAh cm−2. And great rate capability and excellent cyclability can be achieved for full batteries even under harsh conditions. This work provides new insights into separator design for Zn-based batteries.
期刊介绍:
The Journal of Energy Chemistry, the official publication of Science Press and the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, serves as a platform for reporting creative research and innovative applications in energy chemistry. It mainly reports on creative researches and innovative applications of chemical conversions of fossil energy, carbon dioxide, electrochemical energy and hydrogen energy, as well as the conversions of biomass and solar energy related with chemical issues to promote academic exchanges in the field of energy chemistry and to accelerate the exploration, research and development of energy science and technologies.
This journal focuses on original research papers covering various topics within energy chemistry worldwide, including:
Optimized utilization of fossil energy
Hydrogen energy
Conversion and storage of electrochemical energy
Capture, storage, and chemical conversion of carbon dioxide
Materials and nanotechnologies for energy conversion and storage
Chemistry in biomass conversion
Chemistry in the utilization of solar energy