Ionothermal synthesis and electrochemical properties of a selenidostannate containing the mixed cations of Na+ and enH+

• A 2D selenidostannate interconnected by sodium ions to form a 3D structure.
• The selenidostannate containing the mixed cations of Na+ and enH+.
• The compound shows a Na+ ion storage property without capacity fading over 150 cycles.

In this report, by taking advantages of the competitive and synergistic effects of mixed-cations under the ionothermal conditions, a novel selenidostannate compound containing the mixed cations, namely (enH)3Na[Sn3Se7]2·1.5Me2NH·1.5H2O (1, en=ethylenediamine, Me2NH=dimethylamine) was obtained in the presence of the ionic liquid (IL) [DAMS]I (4-N,N-Dimethylamino-4′-N′-methylstilbazolium iodide) with a bulky and more structurally rigid organic cation as the main solvent and en as the auxiliary solvent. The compound features anionic [Sn3Se7]n2n- layers that are interconnected by sodium ions to form a three-dimensional (3D) structure. The syntheses, structure, thermal, optical and electrochemical properties of 1 were investigated. 1 showed good thermal stability and a Na+ ion storage property without capacity fading over 150 cycles.

A selenidostannate (enH)3Na[Sn3Se7]2·1.5Me2NH·1.5H2O prepared in the ionic liquid of 4-N,N-Dimethylamino-4′-N′-methylstilbazolium iodide exhibited the reversible Na-ion storage property.Figure optionsDownload as PowerPoint slide