Hongwei Liao

Room-temperature conversion route to nanocrystalline mercury chalcogenides HgE (E = S, Se, Te)

Abstract A convenient, simple route has been employed to synthesize the nanocrystalline HgE (E=S,Se,Te) in ethylenediamine at room temperature. Mercury oxide was used as mercury source and sulfur, selenium, tellerium, respectively, as chalcogenide sources. The obtained products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) techniques. XRD patterns show that the products were hexagonal (wurtzite structure) HgS, cubic (zincblende structure) HgSe and HgTe. We also find that the ethylenediamine plays a crucial role in the conversion process.

Hydrothermal Synthesis of Ultrafine α-Fe2O3 and Fe3O4 Powders

Ultrafine α-Fe2O3 and Fe3O4 particles were prepared through a hydrothermal process at 150°C from a (NH4)2SO4·FeSO4·6H2O solution in the presence of hydrazine. These products were characterized by X-ray diffraction and transmission electron microscopy. The formation of pure α-Fe2O3 and Fe3O4 powders was strongly influenced by the pH values of the aqueous solution.