Thermal decomposition of precursor gel and crystalline mechanism of BeO nanopowders synthesized by polyacrylamide gel method

The BeO nanopowders were synthesized by the polyacrylamide gel method.The thermal decomposition process of precious gel and the properties of the obtained powder were investigated by TG-DSC,XRD and SEM,and the crystalline mechanism of nano-BeO in the thermal decomposition process was indicated by growth units model theory of anion coordination polyhedron.The results show that the organic gel in the precious gel is disintegrated gradually,and meanwhile the crystal water of the beryllium sulfate salt in precious gel is removed with the increase of temperature;when the temperature is about 600 ℃,the organic gel is disintegrated completely and nano-BeSO4 is obtained;BeO nanopowders are achieved under higher temperature.During the thermal decomposition of BeSO4 processes,the chemical bonds of its growth units Be(SO4)6-break down and nano-BeO forms,and the process of crystal nucleus formation is heterogeneous nucleation under the forced condition.