% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@ARTICLE{Li:599477,
      author       = {Li, Yongchun and Mazzio, Katherine and Yaqoob, Najma and
                      Sun, Yanan and Freytag, Annica and Wong, Deniz and Schulz,
                      Christian and Baran, Volodymyr and San Jose Mendez, Alba and
                      Schuck, Götz and Zając, Marcin and Kaghazchi, Payam and
                      Adelhelm, Philipp},
      title        = {{C}ompeting mechanisms determine oxygen redox in doped
                      {N}i-{M}n based layered oxides for {N}a-ion batteries},
      reportid     = {PUBDB-2023-07449},
      year         = {2023},
      abstract     = {Cation doping is an effective strategy for improving the
                      cyclability of layered oxide cathode materials through
                      suppression of phase transitions in the high voltage region
                      (>~4.0V). In this study we choose Mg and Sc as
                      representative dopants in P2-
                      Na$_{0.67}$Ni$_{0.33}$Mn$_{0.67}$O$_2$. While both dopants
                      have a positive effect on the cycling stability, they are
                      found to influence the properties in the high voltage regime
                      in different ways. Through a combination of RIXS, XRD, XAS,
                      PDF analysis, and DFT, we show that it is more than just
                      suppression of the P2 to O$_2$ phase transition that is
                      critical for promoting the favorable properties, and that
                      the interplay between Ni and O activity are also critical
                      aspects that dictate the performance. With Mg doping, we
                      could enhance the Ni activity while simultaneously
                      suppressing the O activity. This is surprising because it is
                      in contrast to what has been reported in other Mn-based
                      layered oxides where Mg is known to trigger oxygen redox. We
                      address this contradiction by proposing a competing
                      mechanism between Ni and Mg that impacts differences in O
                      activity in Na$_{0.67}$Mg$_x$Ni$_{0.33-x}$Mn$_{0.67}$O$_2$
                      (x<0<0.33). These findings provide a new direction in
                      understanding the effects of cation doping on the
                      electrochemical behavior of layered oxides.},
      cin          = {DOOR ; HAS-User / FS-PETRA-D},
      cid          = {I:(DE-H253)HAS-User-20120731 /
                      I:(DE-H253)FS-PETRA-D-20210408},
      pnm          = {632 - Materials – Quantum, Complex and Functional
                      Materials (POF4-632) / 6G3 - PETRA III (DESY) (POF4-6G3)},
      pid          = {G:(DE-HGF)POF4-632 / G:(DE-HGF)POF4-6G3},
      experiment   = {EXP:(DE-H253)P-P02.1-20150101},
      typ          = {PUB:(DE-HGF)25},
      doi          = {10.26434/chemrxiv-2023-jfnmr},
      url          = {https://bib-pubdb1.desy.de/record/599477},
}