Rodlike ammonium tetrathiomolybdate has been synthesized via ultrasonic assistance using monocrystal ammonium dimolybdate and ammonium sulfide as raw materials. The phase compositions, purity of as-synthesized products were characterized by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), laser Raman spectroscopy(LRS). The thermal decomposition mechanism of ammonium tetrathiomolybdate was deduced by thermoanalysis. It is shown that brownish-red rhombic ammonium tetrathiomolybdate crystal with high purity could be obtained at 60°C for 1h under relatively mild conditions.

The nanosized silica with different morphologies such as sphere, granule, needle, short rod, hollow tubule, has been in turn synthesized by using cetyltrimethylammonium bromide (CTAB) as template and mixed chlorosilane (silicon tetrachloride and trichlorosilane) as silicon source in aliphatic alcohol aqueous solution. The as-prepared products were characterized by x-ray diffraction (XRD), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FT-IR), and BET nitrogen adsorption technique was employed for determination of specific surface area of the powdery silica. The formation conditions and mechanism of the nanosized silica with special and diverse shapes are preliminarily discussed.