Powered by OpenAIRE graph
Found an issue? Give us feedback
addClaim

This Research product is the result of merged Research products in OpenAIRE.

You have already added 0 works in your ORCID record related to the merged Research product.

A First-Principles Investigation of the Role Played by Oxygen Deficiency in the Electrochemical Properties of LiCu[sub 0.5]Mn[sub 1.5]O[sub 4−δ] Spinels

Authors: J. Morales; M. E. Arroyo y de Dompablo; M. E. Arroyo y de Dompablo;

A First-Principles Investigation of the Role Played by Oxygen Deficiency in the Electrochemical Properties of LiCu[sub 0.5]Mn[sub 1.5]O[sub 4−δ] Spinels

Abstract

The effect of oxygen deficiency in Cu-based spinels Li[Cu 0.5 Mn 1.5 ] oat O 4-δ was examined using first-principles calculation. Two main results were obtained upon oxygen removal: (i) a progressive unit cell expansion owing to the presence of both more reduced transition metal cation and oxygen vacancies, (ii) a progressive decrease in the average lithium deinsertion voltage as the oxygen deficiency increases. Computational results indicate that the oxygen deficiency gives rise to a partial reduction of Mn 4+ to Mn 3+ , whereas upon lithium deinsertion, this reaction is reversed together with the oxidation of Cu 2+ to diamagnetic Cu 3+ . The electrochemical tests in lithium cells of two spinels with 8 values 0.04 and 0.1 were consistent with these calculations. Computational data indicate that the oxidation of Cu +2 to Cu +3 would be favored in highly oxygen deficient spinels; this contradicts the experimental results that show a decrease of the specific capacity in the high-voltage range with the oxygen deficiency. However, in the prepared spinels, there is an important fraction of Cu ions occupying tetrahedral sites. Therefore, computational investigation points to the electrochemical inactivity of tetrahedral Cu rather than to the oxygen content as the origin of the poor charge capacity observed in the high-voltage range.

  • BIP!
    Impact byBIP!
    citations
    This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    15
    popularity
    This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
    Average
    influence
    This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    Top 10%
    impulse
    This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
    Top 10%
Powered by OpenAIRE graph
Found an issue? Give us feedback
citations
This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Citations provided by BIP!
popularity
This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
BIP!Popularity provided by BIP!
influence
This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Influence provided by BIP!
impulse
This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
BIP!Impulse provided by BIP!
15
Average
Top 10%
Top 10%