Highly Conducting Li(Fe<sub>1−<i>x</i></sub>Mn<sub><i>x</i></sub>)<sub>0.88</sub>V<sub>0.08</sub>PO<sub>4</sub> Cathode Materials Nanocrystallized from the Glassy State (<i>x</i> = 0.25, 0.5, 0.75)
This study showed that thermal nanocrystallization of glassy analogs of LiFe<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mrow><mn>1</mn><mo>−</mo>...
Guardado en:
| Autores principales: | , |
|---|---|
| Formato: | article |
| Lenguaje: | EN |
| Publicado: |
MDPI AG
2021
|
| Materias: | |
| Acceso en línea: | https://doaj.org/article/74a7cb78d570406fb838bb2c4395a0ec |
| Etiquetas: |
Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
|
| Sumario: | This study showed that thermal nanocrystallization of glassy analogs of LiFe<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mrow><mn>1</mn><mo>−</mo><mi>x</mi></mrow></msub></semantics></math></inline-formula>Mn<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mi>x</mi></msub></semantics></math></inline-formula>PO<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>4</mn></msub></semantics></math></inline-formula> (with the addition of vanadium for improvement of glass forming properties) resulted in highly conducting materials that may be used as cathodes for Li-ion batteries. The glasses and nanomaterials were studied with differential thermal analysis, X-ray diffractometry, and impedance spectroscopy. The electrical conductivity of the nanocrystalline samples varied, depending on the composition. For <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>x</mi><mo>=</mo><mn>0.5</mn></mrow></semantics></math></inline-formula>, it exceeded <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mn>10</mn><mrow><mo>−</mo><mn>3</mn></mrow></msup></semantics></math></inline-formula> S/cm at room temperature with an activation energy as low as 0.15 eV. The giant and irreversible increase in the conductivity was explained on the basis of Mott’s theory of electron hopping and a core-shell concept. Electrochemical performance of the active material with <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>x</mi><mo>=</mo><mn>0.5</mn></mrow></semantics></math></inline-formula> was also reported. |
|---|