Synthesis and structural characterization of fi-(NH4)2Mo4O13 by direct "reducing ammonium" in situ transformation method

A new environmentally friendly strategy for the synthesis of fi-(NH4)2Mo4O13 powders is presented using a direct "reducing ammonium" in situ transformation method from (NH4)2Mo2O7. The crystal structure of the resulting fi-(NH4)2Mo4O13 was first characterized using X-ray diffraction analysis. The title compound crystallizes in a triclinic system, space Group P-1(2), a = 8.250 angstrom, b = 8.331 angstrom, c = 10.240 angstrom, a = 104.686 degrees, fi = 106.077 degrees, y = 109.614 degrees, Z = 2. The TG-DTA results showed that no intermediate products were generated in the thermal decomposition process from fi-(NH4)2Mo4O13 to MoO3. A comprehensive study of the newly synthesized fi-(NH4)2Mo4O13 was performed by FESEM, FTIR spectroscopy and Raman spectroscopy. The band gap energy of the synthesizedfi-(NH4)2Mo4O13 was 3.26 eV, which shows a good intense absorption band in the visible light region.