مورد إلكتروني
Exploring the charge compensation mechanism of P2-type Na0.6Mg0.3Mn0.7O2 cathode materials for advanced sodium-ion batteries
| العنوان: | Exploring the charge compensation mechanism of P2-type Na0.6Mg0.3Mn0.7O2 cathode materials for advanced sodium-ion batteries |
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| المؤلفون: | Cheng, C, Cheng, C, Ding, M, Yan, T, Dai, K, Mao, J, Zhang, N, Zhang, L, Guo, J |
| المصدر: | Energies; vol 13, iss 21, 5729-5729; 1996-1073 |
| بيانات النشر: | eScholarship, University of California 2020-11-01 |
| نوع الوثيقة: | Electronic Resource |
| مستخلص: | P2-type sodium layered transition metal oxides have been intensively investigated as promising cathode materials for sodium-ion batteries (SIBs) by virtue of their high specific capacity and high operating voltage. However, they suffer from problems of voltage decay, capacity fading, and structural deterioration, which hinder their practical application. Therefore, a mechanistic understanding of the cationic/anionic redox activity and capacity fading is indispensable for the further improvement of electrochemical performance. Here, a prototype cathode material of P2-type Na0.6Mg0.3Mn0.7O2 is comprehensively investigated, which presents both cationic and anionic redox behaviors during the cycling process. By a combination of soft X-ray absorption spectroscopy and electroanalytical methods, we unambiguously reveal that only oxygen redox reaction is involved in the initial charge process, then both oxygen and manganese participate in the charge compensation in the following discharge process. In addition, a gradient distribution of Mn valence state from surface to bulk is disclosed, which could be mainly related to the irreversible oxygen activity during the charge process. Furthermore, we find that the average oxidation state of Mn is reduced upon extended cycles, leading to the noticeable capacity fading. Our results provide deeper insights into the intrinsic cationic/anionic redox mechanism of P2-type materials, which is vital for the rational design and optimization of advanced cathode materials for SIBs. |
| مصطلحات الفهرس: | sodium-ion batteries, P2-tpye oxides, charge compensation mechanism, X-ray absorption spectroscopy, electronic structure, Affordable and Clean Energy, Physical Sciences, Engineering, article |
| URL: | |
| الإتاحة: | Open access content. Open access content public |
| ملاحظة: | application/pdf Energies vol 13, iss 21, 5729-5729 1996-1073 |
| أرقام أخرى: | CDLER oai:escholarship.org:ark:/13030/qt55r0d5qq qt55r0d5qq https://escholarship.org/uc/item/55r0d5qq https://escholarship.org/ 1367394628 |
| المصدر المساهم: | UC MASS DIGITIZATION From OAIster®, provided by the OCLC Cooperative. |
| رقم الأكسشن: | edsoai.on1367394628 |
| قاعدة البيانات: | OAIster |
| الوصف غير متاح. |