Synthesis of nanocrystalline marcasite iron ditelluride FeTe2 in aqueous solution

Reaction of an alkaline aqueous solution dissolving elemental tellurium and iron(II) complex Na-2[Fe(EDTA)] aqueous solution produces nanocrystalline marcasite FeTe2 at 140 degreesC under atmospheric pressure. All peaks in th e XRD pattern of the final product can be indexed to orthorhombic FeTe2 wit h the cell constants a = 5.31 Angstrom, b = 6.29 Angstrom and c = 3.86 Angs trom. TEM image of FeTe2 nanocrystallites shows an average particle size of 25 nm with a spherical morphology. The tellurium alkaline solution, as a t ellurium source, makes FeTe2 crystallize well in aqueous solution. The use of iron(II) complex instead of iron(II) ion greatly reduced the amount of b yproduct. The mechanism of the formation of iron ditelluride was discussed. (C) 2001 Elsevier Science B.V. All rights reserved.