{"title":"点缺陷对镍铁氧体 NiFe2O4 中电荷传输的影响","authors":"","doi":"10.1016/j.commatsci.2024.113326","DOIUrl":null,"url":null,"abstract":"<div><p>The paper considers electronic structure of pristine and defective nickel ferrite (spinel <span><math><mrow><mtext>Ni</mtext><msub><mrow><mtext>Fe</mtext></mrow><mrow><mn>2</mn></mrow></msub><msub><mrow><mtext>O</mtext></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>). The orbital ordering, band gap and charge transfer are studied in the framework of density functional theory with account of strong electronic correlations (DFT+U method). The possibility of changing the type of polaron transport in the presence of oxygen vacancies and nickel antisites has been demonstrated. The corresponding non-adiabatic activation barriers of polaron transport is considered. The resulting hopping energies are in general agreement with experimentally observed activation energies. The highlighted influence of point defects on the polaron conductivity mechanism could be a suitable explanation for the large variability of activation energies in previous experimental works. NEGF-DFT calculations were also performed to consider a possible band conduction mechanism. The enhanced conduction with the presence of oxygen bi-vacancies, and a change in carrier type is also observed.</p></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":null,"pages":null},"PeriodicalIF":3.1000,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Influence of point defects on charge transport in nickel ferrite NiFe2O4\",\"authors\":\"\",\"doi\":\"10.1016/j.commatsci.2024.113326\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The paper considers electronic structure of pristine and defective nickel ferrite (spinel <span><math><mrow><mtext>Ni</mtext><msub><mrow><mtext>Fe</mtext></mrow><mrow><mn>2</mn></mrow></msub><msub><mrow><mtext>O</mtext></mrow><mrow><mn>4</mn></mrow></msub></mrow></math></span>). The orbital ordering, band gap and charge transfer are studied in the framework of density functional theory with account of strong electronic correlations (DFT+U method). The possibility of changing the type of polaron transport in the presence of oxygen vacancies and nickel antisites has been demonstrated. The corresponding non-adiabatic activation barriers of polaron transport is considered. The resulting hopping energies are in general agreement with experimentally observed activation energies. The highlighted influence of point defects on the polaron conductivity mechanism could be a suitable explanation for the large variability of activation energies in previous experimental works. NEGF-DFT calculations were also performed to consider a possible band conduction mechanism. The enhanced conduction with the presence of oxygen bi-vacancies, and a change in carrier type is also observed.</p></div>\",\"PeriodicalId\":10650,\"journal\":{\"name\":\"Computational Materials Science\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.1000,\"publicationDate\":\"2024-09-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Computational Materials Science\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0927025624005470\",\"RegionNum\":3,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATERIALS SCIENCE, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Computational Materials Science","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0927025624005470","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
Influence of point defects on charge transport in nickel ferrite NiFe2O4
The paper considers electronic structure of pristine and defective nickel ferrite (spinel ). The orbital ordering, band gap and charge transfer are studied in the framework of density functional theory with account of strong electronic correlations (DFT+U method). The possibility of changing the type of polaron transport in the presence of oxygen vacancies and nickel antisites has been demonstrated. The corresponding non-adiabatic activation barriers of polaron transport is considered. The resulting hopping energies are in general agreement with experimentally observed activation energies. The highlighted influence of point defects on the polaron conductivity mechanism could be a suitable explanation for the large variability of activation energies in previous experimental works. NEGF-DFT calculations were also performed to consider a possible band conduction mechanism. The enhanced conduction with the presence of oxygen bi-vacancies, and a change in carrier type is also observed.
期刊介绍:
The goal of Computational Materials Science is to report on results that provide new or unique insights into, or significantly expand our understanding of, the properties of materials or phenomena associated with their design, synthesis, processing, characterization, and utilization. To be relevant to the journal, the results should be applied or applicable to specific material systems that are discussed within the submission.