National Synchrotron Light Source Lunch Time Seminar

Layered transition metal oxides of α-NaFeO2-type structure have been
> of historical interest from both theoretical and experimental
> point-of- views. For instance, LiNiO2 was initially predicted as being
> the first realization of a spin liquid. Even though a spin liquid
> state has not been realized in LiNiO2, the magnetic ground state (in
> this and other equi-structural materials) has been controversial and
> is currently under considerable investigation.
> Interests in Li-
> layered compounds have also prompted a tremendous research effort due
> to their application in Li-ion batteries. Where one seeks to partially
> or in full replace Co in the LiCoO2 cathode with other transition
> metal (TM) ions while maintaining the structural stability and
> increasing the capacity. The replacement is primarily motivated by
> cost and environmental concerns regarding Co.
>
> The magnetic properties in several compounds of Li(NixCoyMnz)O2 have
> been investigated through SQUID magnetometry, neutron diffraction and
> muon-SR.
> The materials show a ferrimagnetic re-entrant cluster glass behaviour
> with spin frustration in both 2 and 3 dimensions. The magnetic
> behaviour is believed to originate from the degree of cationic mixing
> (Ni2+ in the Li-layer), the TM- distribution, as well as the magnetic
> cluster size in the material.
> Additionally, a
> possible link between low temperature magnetic order and frustration
> and cathode performance at room temperature will be presented.
>
> [1] J. M. Wikberg et al. Physics Procedia, in print (2011) [2] J. M.
> Wikberg et al. J. Appl. Phys., 180 083909 (2010) [3] J. M. Wikberg et
> al. Phys. Rev. B, 81 224411 (2010)
>
>
>
>