We synthesized Ba(Ti_(1-x)Zr_(x))O_(3)-based(BTZ)nanopowders modified with Cu and Nb,and sintered ceramics using a one-step sol-gel process.Characterization using TG-DTG,XRD,SEM,and TEM analysis methods revealed that ...We synthesized Ba(Ti_(1-x)Zr_(x))O_(3)-based(BTZ)nanopowders modified with Cu and Nb,and sintered ceramics using a one-step sol-gel process.Characterization using TG-DTG,XRD,SEM,and TEM analysis methods revealed that the powders formed at a nanometer scale.The process was controlled by the composition and calcining temperature.BaZrO3 formed earlier than BaTiO3 during the calcining,then a Ba(Ti_(1-x)Zr_(x))O_(3) solid solution formed incompletely,resulting in ceramics with huge permittivity and good temperature stability.Moreover,the maximum dielectric constant(εmax)first increased and then decreased as the Curie temperature(Tc)shifted to a lower temperature.When the Zr concentration was 5.4 mol%,εmax was greater than 24,000 and the dielectric loss(25℃)was only 0.005;this meets the Electronic Industries Alliance Y5V specifications.These nanopowders would permit a significant reduction in the thickness of multilayer ceramic capacitors and the huge pemittivity of the ceramics will help meet the current demand for device miniaturization in the electronics industry.展开更多
基金supported by the scientific research and projects program of the National Natural Science Foundation of China(No.21071115)by the Education Committee of Shaanxi province(No.09JC01).
文摘We synthesized Ba(Ti_(1-x)Zr_(x))O_(3)-based(BTZ)nanopowders modified with Cu and Nb,and sintered ceramics using a one-step sol-gel process.Characterization using TG-DTG,XRD,SEM,and TEM analysis methods revealed that the powders formed at a nanometer scale.The process was controlled by the composition and calcining temperature.BaZrO3 formed earlier than BaTiO3 during the calcining,then a Ba(Ti_(1-x)Zr_(x))O_(3) solid solution formed incompletely,resulting in ceramics with huge permittivity and good temperature stability.Moreover,the maximum dielectric constant(εmax)first increased and then decreased as the Curie temperature(Tc)shifted to a lower temperature.When the Zr concentration was 5.4 mol%,εmax was greater than 24,000 and the dielectric loss(25℃)was only 0.005;this meets the Electronic Industries Alliance Y5V specifications.These nanopowders would permit a significant reduction in the thickness of multilayer ceramic capacitors and the huge pemittivity of the ceramics will help meet the current demand for device miniaturization in the electronics industry.
