Integrated process of large-scale and size-controlled SnO2 nanoparticles by hydrothermal method

SnO2 nanoparticles with the average particle size of 5–30 nm were synthesized using SnCl4·5H2O as the precursor and NH3·H2O as the mineralizing agent by hydrothermal method. In the case of 1 kg/batch production, the effects of synthesis conditions including solution concentration, reaction temperature, pressure, time and pH value on the grain size, particle morphology and crystal structure of SnO2 were systematically studied. The particles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that, the particle size can be well controlled in the range of 5–30 nm by adjusting the processing parameters such as reaction temperature and time when the crystal structure and particle morphology remain unchanged. The previous reports, the unusual dependences of the grain size of SnO2 on reaction temperature and time were found. The mechanism for such abnormal grain growth behavior was tentatively elucidated.