{"title":"用于对称锂离子电池的 Li2FeTiO4/C/G 纳米纤维中的超细纳米粒子和石墨烯对离子/电子传输的协同增强作用","authors":"","doi":"10.1016/j.jechem.2024.09.031","DOIUrl":null,"url":null,"abstract":"<div><div>Low-cost Fe-based disordered rock salt (DRX) Li<sub>2</sub>FeTiO<sub>4</sub> is capable of providing high capacity (295 mA h g<sup>−1</sup>) by redox activity of cations (Fe<sup>2+</sup>/Fe<sup>4+</sup> and Ti<sup>3+</sup>/Ti<sup>4+</sup>) and anionic oxygen. However, DRX structures lack transport channels for ions and electrons, resulting in sluggish kinetics, poor electrochemical activity, and cyclability. Herein, graphene conductive carbon network permeated Li<sub>2</sub>FeTiO<sub>4</sub> (LFT/C/G) nanofibers are successfully prepared by a facile sol-gel assisted electrospinning method. Ultrafine Li<sub>2</sub>FeTiO<sub>4</sub> nanoparticles (2 nm) and one-dimensional (1D) structure provide abundant active sites and unobstructed diffusion channels, accelerating ion diffusion. In addition, introducing graphene reduces the band gap and Li<sup>+</sup> diffusion barrier and improves the dynamic properties of Li<sub>2</sub>FeTiO<sub>4</sub>, thus achieving a relatively mild interfacial reaction and reversible redox reaction. As expected, the LFT/C/1.0G cathode delivers a remarkable discharge capacity (238.5 mA h g<sup>−1</sup>), high energy density (508.8 Wh kg<sup>−1</sup>), and excellent rate capability (51.2 mA h g<sup>−1</sup> at 1.0 A g<sup>−1</sup>). Besides, the LFT/C/1.0G anode also displays a high capacity (514.5 mA h g<sup>−1</sup> at 500 mA g<sup>−1</sup>) and a remarkable rate capability (243.9 mA h g<sup>−1</sup> at 8 A g<sup>−1</sup>). Moreover, the full batteries based on the LFT/C/1.0G symmetric electrode demonstrate a reversible capacity of 117.0 mA h g<sup>−1</sup> after 100 cycles at 50 mA g<sup>−1</sup>. This study presents useful insights into developing cost-effective DRX cathodes with durable and fast lithium storage.</div></div>","PeriodicalId":15728,"journal":{"name":"Journal of Energy Chemistry","volume":null,"pages":null},"PeriodicalIF":13.1000,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Synergistic enhancement of ion/electron transport by ultrafine nanoparticles and graphene in Li2FeTiO4/C/G nanofibers for symmetric Li-ion batteries\",\"authors\":\"\",\"doi\":\"10.1016/j.jechem.2024.09.031\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Low-cost Fe-based disordered rock salt (DRX) Li<sub>2</sub>FeTiO<sub>4</sub> is capable of providing high capacity (295 mA h g<sup>−1</sup>) by redox activity of cations (Fe<sup>2+</sup>/Fe<sup>4+</sup> and Ti<sup>3+</sup>/Ti<sup>4+</sup>) and anionic oxygen. However, DRX structures lack transport channels for ions and electrons, resulting in sluggish kinetics, poor electrochemical activity, and cyclability. Herein, graphene conductive carbon network permeated Li<sub>2</sub>FeTiO<sub>4</sub> (LFT/C/G) nanofibers are successfully prepared by a facile sol-gel assisted electrospinning method. Ultrafine Li<sub>2</sub>FeTiO<sub>4</sub> nanoparticles (2 nm) and one-dimensional (1D) structure provide abundant active sites and unobstructed diffusion channels, accelerating ion diffusion. In addition, introducing graphene reduces the band gap and Li<sup>+</sup> diffusion barrier and improves the dynamic properties of Li<sub>2</sub>FeTiO<sub>4</sub>, thus achieving a relatively mild interfacial reaction and reversible redox reaction. As expected, the LFT/C/1.0G cathode delivers a remarkable discharge capacity (238.5 mA h g<sup>−1</sup>), high energy density (508.8 Wh kg<sup>−1</sup>), and excellent rate capability (51.2 mA h g<sup>−1</sup> at 1.0 A g<sup>−1</sup>). Besides, the LFT/C/1.0G anode also displays a high capacity (514.5 mA h g<sup>−1</sup> at 500 mA g<sup>−1</sup>) and a remarkable rate capability (243.9 mA h g<sup>−1</sup> at 8 A g<sup>−1</sup>). Moreover, the full batteries based on the LFT/C/1.0G symmetric electrode demonstrate a reversible capacity of 117.0 mA h g<sup>−1</sup> after 100 cycles at 50 mA g<sup>−1</sup>. This study presents useful insights into developing cost-effective DRX cathodes with durable and fast lithium storage.</div></div>\",\"PeriodicalId\":15728,\"journal\":{\"name\":\"Journal of Energy Chemistry\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":13.1000,\"publicationDate\":\"2024-09-28\",\"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/S2095495624006557\",\"RegionNum\":1,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"Energy\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Energy Chemistry","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2095495624006557","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
摘要
低成本的铁基无序岩盐(DRX)Li2FeTiO4 能够通过阳离子(Fe2+/Fe4+ 和 Ti3+/Ti4+)和阴离子氧的氧化还原活动提供高容量(295 mA h g-1)。然而,DRX 结构缺乏离子和电子的传输通道,导致动力学缓慢、电化学活性和可循环性差。本文采用溶胶-凝胶辅助电纺丝方法,成功制备了石墨烯导电碳网络渗透 Li2FeTiO4(LFT/C/G)纳米纤维。超细的 Li2FeTiO4 纳米颗粒(2 nm)和一维(1D)结构提供了丰富的活性位点和畅通的扩散通道,加速了离子扩散。此外,石墨烯的引入降低了带隙和 Li+ 扩散阻力,改善了 Li2FeTiO4 的动态特性,从而实现了相对温和的界面反应和可逆氧化还原反应。正如预期的那样,LFT/C/1.0G 阴极具有显著的放电容量(238.5 mA h g-1)、高能量密度(508.8 Wh kg-1)和出色的速率能力(51.2 mA h g-1,1.0 A g-1)。此外,LFT/C/1.0G 阳极也显示出较高的容量(500 mA g-1 时为 514.5 mA h g-1)和出色的速率能力(8 A g-1 时为 243.9 mA h g-1)。此外,基于 LFT/C/1.0G 对称电极的全电池在 50 mA g-1 条件下循环 100 次后,显示出 117.0 mA h g-1 的可逆容量。这项研究为开发具有持久和快速锂存储能力的高性价比 DRX 阴极提供了有益的启示。
Synergistic enhancement of ion/electron transport by ultrafine nanoparticles and graphene in Li2FeTiO4/C/G nanofibers for symmetric Li-ion batteries
Low-cost Fe-based disordered rock salt (DRX) Li2FeTiO4 is capable of providing high capacity (295 mA h g−1) by redox activity of cations (Fe2+/Fe4+ and Ti3+/Ti4+) and anionic oxygen. However, DRX structures lack transport channels for ions and electrons, resulting in sluggish kinetics, poor electrochemical activity, and cyclability. Herein, graphene conductive carbon network permeated Li2FeTiO4 (LFT/C/G) nanofibers are successfully prepared by a facile sol-gel assisted electrospinning method. Ultrafine Li2FeTiO4 nanoparticles (2 nm) and one-dimensional (1D) structure provide abundant active sites and unobstructed diffusion channels, accelerating ion diffusion. In addition, introducing graphene reduces the band gap and Li+ diffusion barrier and improves the dynamic properties of Li2FeTiO4, thus achieving a relatively mild interfacial reaction and reversible redox reaction. As expected, the LFT/C/1.0G cathode delivers a remarkable discharge capacity (238.5 mA h g−1), high energy density (508.8 Wh kg−1), and excellent rate capability (51.2 mA h g−1 at 1.0 A g−1). Besides, the LFT/C/1.0G anode also displays a high capacity (514.5 mA h g−1 at 500 mA g−1) and a remarkable rate capability (243.9 mA h g−1 at 8 A g−1). Moreover, the full batteries based on the LFT/C/1.0G symmetric electrode demonstrate a reversible capacity of 117.0 mA h g−1 after 100 cycles at 50 mA g−1. This study presents useful insights into developing cost-effective DRX cathodes with durable and fast lithium storage.
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