Controlled synthesis of octahedral jarosite
Octahedral jarosite was successfully prepared without extra template using a novel hydrothermal route based on the redox reaction between KMnO4 and (NH4)2Fe(SO4)2·6H2O. The mass ratio of (NH4)2Fe(SO4)2·6H2O/KMnO4, reaction time, and reaction temperature play key roles in forming octahedral crystals. The chemical composition and microstructure of as-prepared octahedral jarosite were characterised by X-ray diffraction, scanning electron microscopy, energy dispersive spectrum, high-resolution transmission electron microscopy, and selective area electron diffraction. The formation mechanism of octahedral jarosite was discussed preliminarily.
