Solvothermal processes to indium selenide precursors and their conversion to phase-pure polycrystalline In2Se3

Two indium selenide precursors were solvothermally synthesized in ethylened iamine (en) and hydrazine hydrate with indium powder (or InCl3.4H(2)O) and selenium under 190 degrees. After decomposition at 300 degrees for five hou rs under flowing argon, the two precursors gave phase-pure polycrystalline In2Se3. The two precursors and the final product were characterized by TGA, X-ray fluorescence spectroscopy, X-ray diffraction pattern (XRD), transmis sion electron microscopy (TEM), UV-vis, FTIR and Raman spectroscopy. In the en system, white phosphorus must be added to ensure the completion of the reaction. As to the hydrazine hydrate system, besides solvent and complex a gent, it also acts as reductive in one case.