A theoretical framework for oxygen redox chemistry for sustainable batteries

An interactive design for sustainable oxygen capacity in alkali-ion batteries

“…This could be attributed to the presence of an O(2p) electronic population at the edge of the valence band, and the similar electronic structure was also observed in Li-excess Na oxide. 16,17,23 As shown by the PDOSs at x = 0.625, further delithiation did not change the charge state of Mn 4+ , whereas the oxidized O(2p) electron appeared in the conduction band. These results underpin the claim that oxygen ions are a key factor in the charge-compensation mechanism for x > 0.125.…”

“…Although these studies suggested some potential improvement owing to doping, coating, and building composites, serious challenges remain since it has not been known yet how to rationally utilize the pure anionic redox capacity of Li 2 MnO 3 sustainably. [7][8][9][10][11][12][13][14][15][16] Therefore, novel approaches to exploiting the oxygen performance of Li 2 MnO 3 are needed.…”

Design and Development of Cathode Materials for Rechargeable Batteries

“…However, Li-rich layered oxides electrodes suffer from severe voltage fade and hysteresis problems, which have been linked to electrode structural degradation [8]. Interestingly, recent research has identified intrinsic links between the oxygen redox mechanism and the structural degradation mechanism [9], and various engineering strategies have been developed to address voltage depression problems based on these such understandings. In addition to electrodes with a layered-type structure, some research groups have attempted to develop cationic disordered rocksalt oxide cathodes (DRX) for which there is no need to restrict the type of transition metals used to maintain the layered structure [10].…”

Correlating Mg Displacement with Topologically Regulated Lattice Oxygen Redox in Na-Ion Layered Oxide Cathodes

“…Invoking lattice oxygen redox (LOR) in Mn-based oxide cathodes has long been considered as a viable strategy for boosting the energy density of rechargeable batteries. − Recent investigations on P2-Na 0.67 Mg 0.28 Mg 0.72 O 2 , P2-Na 0.67 Zn 0.22 Mn 0.78 O 2 , and P3-Na 2 Mn 3 O 7 have elucidated that LOR is not confined to alkali-ion systems but can also be invoked in materials with inactive divalent ions, such as Mg 2+ and Zn 2+ , or native Mn vacancies. − However, LOR in these materials is frequently encountered with irreversible lattice oxygen loss and local structural transformation, which results in long-term voltage fade, notable voltage hysteresis, or wretched cycling stability. ,, Multifarious proposals have been built to describe the LOR, including the localized O holes, , OO dimerization, , reductive coupling, , ligand-to-metal charge transfer, , π redox, and O 2 trapped in bulk. − However, a clear-cut correlation between LOR in oxide cathodes with topological structures has not yet been definitively established.…”

“…4−6 However, LOR in these materials is frequently encountered with irreversible lattice oxygen loss and local structural transformation, which results in long-term voltage fade, notable voltage hysteresis, or wretched cycling stability. 1,7,8 Multifarious proposals have been built to describe the LOR, including the localized O holes, 9,10 O�O dimerization, 11,12 reductive coupling, 13,14 ligand-to-metal charge transfer, 15,16 π redox, 17 and O 2 trapped in bulk. 18−20 However, a clear-cut correlation between LOR in oxide cathodes with topological structures has not yet been definitively established.…”