TY - JOUR
T1 - Unveiling the role of Mn-interstitial defect and particle size on the Jahn-Teller distortion of the LiMn2O4 cathode material
AU - Arabolla Rodríguez, Renier
AU - Della Santina Mohallem, Nelcy
AU - Avila Santos, Manuel
AU - Sena Costa, Demetrio A.
AU - Andrey Montoro, Luciano
AU - Mosqueda Laffita, Yodalgis
AU - Tavera Carrasco, Luis A.
AU - Perez-Cappe, Eduardo L.
N1 - Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/4/1
Y1 - 2021/4/1
N2 - This work proposes to unveil the underlying effect of Mn-interstitial defect as well as the particle size on the Jahn Teller distortion. Mn-interstitial defects and nanometric particles were characterized by HRTEM, Rietveld fitting and microstrain XRD analysis. The research was conducted by measuring the changes of the Fermi level, entropy, enthalpy and the redox potential due to the JT transition. Other dynamic electrochemical measurements were also carried out. The structural and microstructural measurements led to propose the presence of Mn ions in distorted tetrahedral 48f positions after using irradiation to induce Mn-interstitial defects. By using the proposed methodology it was possible to experimentally observe that this defect vanishes the JT effect and diminishes the shifting of the Fermi level during the phase transition. Subtle correlations between the capacity of the 3V region and the redox potential drop of these materials were revealed and explained. The surface pressure and bonding effects were set as important factors underlying stunning electrochemical and structural changes that characterise nanometric particles below 15 nm.
AB - This work proposes to unveil the underlying effect of Mn-interstitial defect as well as the particle size on the Jahn Teller distortion. Mn-interstitial defects and nanometric particles were characterized by HRTEM, Rietveld fitting and microstrain XRD analysis. The research was conducted by measuring the changes of the Fermi level, entropy, enthalpy and the redox potential due to the JT transition. Other dynamic electrochemical measurements were also carried out. The structural and microstructural measurements led to propose the presence of Mn ions in distorted tetrahedral 48f positions after using irradiation to induce Mn-interstitial defects. By using the proposed methodology it was possible to experimentally observe that this defect vanishes the JT effect and diminishes the shifting of the Fermi level during the phase transition. Subtle correlations between the capacity of the 3V region and the redox potential drop of these materials were revealed and explained. The surface pressure and bonding effects were set as important factors underlying stunning electrochemical and structural changes that characterise nanometric particles below 15 nm.
KW - Defects
KW - Fermi level
KW - Jahn-Teller effect
KW - LiMnO
KW - Nano-size effect
KW - Surface pressure
UR - http://www.scopus.com/inward/record.url?scp=85100044414&partnerID=8YFLogxK
U2 - 10.1016/j.jpowsour.2021.229519
DO - 10.1016/j.jpowsour.2021.229519
M3 - Artículo
AN - SCOPUS:85100044414
SN - 0378-7753
VL - 490
JO - Journal of Power Sources
JF - Journal of Power Sources
M1 - 229519
ER -