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The microstructures, dielectric properties and energy storage properties of strontium barium niobate based glass-ceramics have been studied as a function of the CeO2 concentration.The XRD results show that the tetragonal tungsten-bronze structured phase is related to Sr0.5Ba0.5Nb2O6 and SrNb2O6 for the un-doped glass-ceramic sample.In these samples with CeO2 addition, there is only one crystalline phase (Sr0.5Ba0.5Nb2O6).The addition of CeO2 suppresses the formation of the secondary phase SrNb2O6.The SEM observations reveal that the addition of CeO2 in the glass significantly changes the microstructure morphology of the glass-ceramics, i.e.adding appropriate content of CeO2 can modify the microstructure of the resulting glass-ceramics by refining grain.However, further addition of CeO2 is adverse to the uniform and dense microstructure for glass-ceramics.The CeO2 concentration evidently affects the dielectric properties and dielectric breakdown strength.The CeO2 concentration dependence of energy storage densities has first increased with increasing CeO2 concentration (0-0.5 mol.%) and then decreased at higher CeO2 concentrations.Typically, glass-ceramic with 0.5mol% CeO2 treated at 850℃C for 3 h possesses optimal energy storage density of 1.95 J/cm3, which is promising dielectric materials for high energy storage capacitor applications.