Transformation of molten SnCl2 to SnO2 nano-single crystals

The phase transformation behaviour of SnCl2 in air during non-isothermal heating has been studied using thermal analysis techniques, complemented by electron microscopy and X-ray diffraction analysis. At a heating rate of 5 °C min−1, molten SnCl2 evaporated at temperatures much lower than its normal boiling point in a flow of air. It was found that the evaporation of molten SnCl2 does not proceed to completion, and is followed by the oxidation reaction which led to the formation of SnO2 nanoparticles with a perfect single crystalline structure. The morphology of obtained SnO2 particles varied at different temperatures, from individual nanocrystals of 20–120 nm in diameter at 600 °C to well shaped micrometer-sized crystals and spherical clusters at 800 °C, and sheet like polycrystals of tens of micrometers in size at 1300 °C.