Structural investigations of α-MnS nanocrystals and thin films synthesised from manganese(II) xanthates by hot injection, solvent-less thermolysis and doctor blade routes.

Manganese (II) xanthate complexes of the form [Mn(S2COR)2(TMEDA)], where TMEDA = tetramethylethylenediamine and R = methyl (1), ethyl (2), n-propyl (3), n-butyl (4), n-pentyl (5), n-hexyl (6) and n-octyl (7), have been synthesised and structures elucidated using single crystal X-ray diffraction. Complexes 1 to 7 were used as molecular precursors to synthesise manganese sulfide (MnS). Olelyamine (OLA) capped nanocrystals have been produced via hot injection, whilst the doctor blading followed by thermolysis yielded thick films. Free-standing polycrystalline powders of MnS are produced by direct thermolysis of precursor powders. All thermolysis techniques produced cubic MnS as confirmed by powder X-ray diffraction, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy and Raman spectroscopy. Magnetic measurements reveal that the α-MnS nanocrystals exhibit ferromagnetic behaviour with a large coercive field strength (e.g., 0.723 kOe for 6.8 nm nanocrystals).