| The transparent and steady Sol of Ba/Ti was synthesized from precursor solution of tetrabutyltitanate, barium acetate and ethanol. Using Fe(NO3)3·9H2O and La(NO3)3·6H2O as doping agents respectively. La3+and Fe3+ were doped on the A or B site of BaTiO3 in the type of Ba(Ti1-xFex)O3 and (Ba1-3xLa2x)(Ti1-3xFe4x)O3, the compositions have been prepared by Sol-gel method. The impact of pH and temperature on BT system is investigated and discussed. y wt% ZnO was added as twice-doped agent to Ba(Ti1-xFex)O3 powders, BaTiO3 powders were coated by (Ba0.97La0.02)(Ti0.97Fe0.04)O3 Sol, Fe3+/ZnOdoped, La3+/Fe3+ doped and sol-coated BaTiO3 ceramics have been prepared with a subsequent different sintering process.Moreover, XRD, TEM, and SEM were used to analyze the composition and microstructure. For the composition of Ba(Ti1-xFex)O3 added y wt% ZnO,ε=1735 andδ=0.51% are reached for x=0.02, y=0.06 in Fe3+/ZnO doped BaTiO3 ceramic at 1kHz and room temperature; For the composition of (Ba1-3xLa2x)(Ti1-3xFe4x)O3, where x=0.0025,εhas a value of 2800, with low temperature coefficient capacitance of 1%, and low dielectric dissipation fraction between 1.8% and 4%, under 1kHz test conditions and at temperature between 0℃and 60℃. For coated specimens, when the mole rate of (Ba0.97La0.02)(Ti0.97Fe0.04)O3 and BaTiO3 is 3/2,εhas a maximum value of 3610 at 60℃, with low temperature coefficient capacitance of 7%, and low dielectric dissipation fraction between 2.1% and 3%, under 1kHz test conditions, at temperature between 0℃and 60℃. On basis of experiments, the relevant causes are also discussed.
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