Research in the Dutton group focuses on the synthesis and characterisation of functional energy materials. I will present results on our work on developing high voltage, high capacity cathodes for Mg-ion batteries and the emergent charges which arise in Ising kagomé lattices. 

Divalent Mg-ion batteries offer an attractive alternative to Li-ion batteries due to the increased capacity offered by cycling a divalent cation and possibility of using a Mg metal anode. Despite demonstration of reversible cycling in the molybdenum sulphide Chevrel phase over 15 years ago[1] improvements have been slow and limiting factors include the lack of a suitable electrolyte and challenges associated with intercalation of Mg²⁺ at high voltages and multiple electron redox on an individual ions. I will present out results on pyro-, Mg_xM_2–xB₂O₅ and orthoborates, Mg_xM_3–x(BO₃)₂M = Mn,Fe,Co,Ni and discuss the role of disorder between Mg and M sites, and the crystal structure on the observed electrochemical properties.[2,3] 

In the second part of the talk I will discuss the novel emergent charge order in Ising kagomé magnets. These are predicted to show formation of a number of exotic states on cooling, which differ significantly from their three dimensional analogue, spin-ice. I will show how 3:1 ordering in pyrochlores, A₃A’B₃B’O₁₄, can be used to generate undistorted kagomé lattices and present results on the Ising system Dy₃Mg₂Sb₃O₁₄. Bulk thermodynamic properties measurements, diffuse scattering and Monte Carlo simulations will be used to demonstrate the existence of emergent charges belowT* ≈100mK.[4]

1. D. Aurbach, Z. Lu, A. Schechter, A., Y. Gofer, H. Gizbar, R. Turgeman, Y. Cohen, M. Moshkovich, and E. Levi, Nature 407, 724 (2000).

2. H. F. J. Glass, Z. Liu, P. M. Bayley, E. Suard, S.-H. Bo, P. G. Khalifah, C. P. Grey, and S. E. Dutton, Chem. Mater. 29, 3118 (2017).

3. H. F. G. Glass et al. in preparation.

4. J. A. M. Paddison, H. S. Ong, J. O. Hamp, P. Mukherjee, X. Bai, M. G. Tucker, N. P. Butch, C. Castelnovo, M. Mourigal, and S. E. Dutton, Nat. Commun. 7, 13842 (2016).