{"title":"Li-Modified BaCoO3-δ for Thermochemical Energy Storage: Enhanced Reaction Performance and Modification Mechanism","authors":"Zeyu Ning, Changdong Gu, Yibin He, Haoran Xu, Peiwang Zhu, Jinsong Zhou, Gang Xiao","doi":"10.1039/d4ta05176a","DOIUrl":null,"url":null,"abstract":"Perovskite materials are promising candidates for thermochemical energy storage, yet conventional substitutional doping has not effectively increased their reactivity at lower temperatures (600-900°C), limiting practical applications. This study synthesized Li-modified BaCoO<small><sub>3-δ</sub></small> to enhance gas-solid reaction activity by introducing structural defects. XRD and ICP analyses confirmed the incorporation of Li into the BaCoO<small><sub>3-δ</sub></small> lattice. TG and DSC experiments demonstrated that Li doping significantly improved the redox activity of the material within the 600-900°C range, increasing the thermochemical storage density by approximately 75% from 199.1 kJ/kg to 348.4 kJ/kg. Van’t Hoff analysis indicates that Li doping increases the entropy and enthalpy of the thermochemical reactions. Cycling experiments showed stable performance enhancement, maintaining over 95% (and even up to 99%) of activity after 450 cycles, still significantly outperforming fresh BaCoO<small><sub>3-δ</sub></small>. DFT calculations, XPS, and EPR analysis revealed that Li doping stabilizes surface oxygen vacancy structures, increasing surface defect oxygen content and enabling stronger redox reactions at lower temperatures. This study elucidates the mechanism by which Li doping enhances the thermochemical heat storage performance of BaCoO<small><sub>3-δ</sub></small>, providing valuable insights for the design of perovskite materials.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":null,"pages":null},"PeriodicalIF":10.7000,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Materials Chemistry A","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1039/d4ta05176a","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Perovskite materials are promising candidates for thermochemical energy storage, yet conventional substitutional doping has not effectively increased their reactivity at lower temperatures (600-900°C), limiting practical applications. This study synthesized Li-modified BaCoO3-δ to enhance gas-solid reaction activity by introducing structural defects. XRD and ICP analyses confirmed the incorporation of Li into the BaCoO3-δ lattice. TG and DSC experiments demonstrated that Li doping significantly improved the redox activity of the material within the 600-900°C range, increasing the thermochemical storage density by approximately 75% from 199.1 kJ/kg to 348.4 kJ/kg. Van’t Hoff analysis indicates that Li doping increases the entropy and enthalpy of the thermochemical reactions. Cycling experiments showed stable performance enhancement, maintaining over 95% (and even up to 99%) of activity after 450 cycles, still significantly outperforming fresh BaCoO3-δ. DFT calculations, XPS, and EPR analysis revealed that Li doping stabilizes surface oxygen vacancy structures, increasing surface defect oxygen content and enabling stronger redox reactions at lower temperatures. This study elucidates the mechanism by which Li doping enhances the thermochemical heat storage performance of BaCoO3-δ, providing valuable insights for the design of perovskite materials.
期刊介绍:
The Journal of Materials Chemistry A, B & C covers a wide range of high-quality studies in the field of materials chemistry, with each section focusing on specific applications of the materials studied. Journal of Materials Chemistry A emphasizes applications in energy and sustainability, including topics such as artificial photosynthesis, batteries, and fuel cells. Journal of Materials Chemistry B focuses on applications in biology and medicine, while Journal of Materials Chemistry C covers applications in optical, magnetic, and electronic devices. Example topic areas within the scope of Journal of Materials Chemistry A include catalysis, green/sustainable materials, sensors, and water treatment, among others.