1 research outputs found
Controllable Regulation of the Oxygen Redox Process in Lithium–Oxygen Batteries by High-Configuration-Entropy Spinel with an Asymmetric Octahedral Structure
Designing bifunctional electrocatalysts to boost oxygen
redox reactions
is critical for high-performance lithium–oxygen batteries (LOBs).
In this work, high-entropy spinel (Co0.2Mn0.2Ni0.2Fe0.2Cr0.2)3O4 (HEOS) is fabricated by modulating the internal configuration
entropy of spinel and studied as the oxygen electrode catalyst in
LOBs. Under the high-entropy atomic environment, the Co–O octahedron
in spinel undergoes asymmetric deformation, and the reconfiguration
of the electron structure around the Co sites leads to the upward
shift of the d-orbital centers of the Co sites toward the Fermi level,
which is conducive to the strong adsorption of redox intermediate
LiO2 on the surface of the HEOS, ultimately forming a layer
of a highly dispersed Li2O2 thin film. Thin-film
Li2O2 is beneficial for ion diffusion and electron
transfer at the electrode–electrolyte interface, which makes
the product easy to decompose during the charge process, ultimately
accelerating the kinetics of oxygen redox reactions in LOBs. Based
on the above advantages, HEOS-based LOBs deliver high discharge/charge
capacity (12.61/11.72 mAh cm–2) and excellent cyclability
(424 cycles). This work broadens the way for the design of cathode
catalysts to improve oxygen redox kinetics in LOBs