Melting and undercooling of bismuth nanocrystals by solvothermal synthesis

The nanocrystals of bismuth with nanowire and sphere in shape were synthesized by solvothermal process, and it was found that the amount of nanowires would be reduced by the proper choice of the reaction solvents. The crystal structure of the as-prepared nanocrystals was investigated with X-ray diffraction (XRD). The morphology of the nanocrystals was observed with the field emission scanning electron microscope (FE-SEM). Moreover, the melting and solidification processes of the bulk bismuth and as-prepared nanocrystals were comparatively studied with differential scanning calorimetry (DSC). During the solidification process, the nanocrystals showed a larger undercooling, the value of which was about 95 and 31 °C higher than that of the bulk bismuth.