Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First principles investigation of anionic redox in bisulfate lithium
  battery cathodes   The search for an alternative high-voltage polyanionic cathode material for
Li-ion batteries is vital to improve the energy densities beyond the
state-of-the-art, where sulfate frameworks form an important class of
high-voltage cathode materials due to the strong inductive effect of the
S$^{6+}$ ion. Here, we have investigated the mechanism of cationic and/or
anionic redox in Li$_x$M(SO$_4$)$_2$ frameworks (M = Mn, Fe, Co, and Ni and 0
$\leq$ x $\leq$ 2) using density functional calculations. Specifically, we have
used a combination of Hubbard $U$ corrected strongly constrained and
appropriately normed (SCAN+$U$) and generalized gradient approximation
(GGA+$U$) functionals to explore the thermodynamic (polymorph stability),
electrochemical (intercalation voltage), geometric (bond lengths), and
electronic (band gaps, magnetic moments, charge populations, etc.) properties
of the bisulfate frameworks considered. Importantly, we find that the anionic
(cationic) redox process is dominant throughout delithiation in the Ni (Mn)
bisulfate, as verified using our calculated projected density of states, bond
lengths, and on-site magnetic moments. On the other hand, in Fe and Co
bisulfates, cationic redox dominates the initial delithiation (1 $\leq$ x
$\leq$ 2), while anionic redox dominates subsequent delithiation (0 $\leq$ x
$\leq$ 2). In addition, evaluation of the crystal overlap Hamilton population
reveals insignificant bonding between oxidizing O atoms throughout the
delithiation process in the Ni bisulfate, indicating robust battery performance
that is resistant to irreversible oxygen evolution. Finally, we observe both
GGA+$U$ and SCAN+$U$ predictions are in qualitative agreement for the various
properties predicted. Our work should open new avenues for exploring lattice
oxygen redox in novel high voltage polyanionic cathodes, especially using the
SCAN+$U$ functional.

15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
2
The categories of this paper are: math
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
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The categories of this paper are: bayes-an
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The categories of this paper are: stat
25
The categories of this paper are: patt-sol