Effect of Co doping on microstructure, dielectric, and energy storage properties of BCZT ceramics

Ba0.85Ca0.15Zr0.1(Ti1−xCox)0.9O3 (BCZT–xCo) (x = 0, 0.02, 0.04, 0.08) were prepared by sol–gel method, and the effects of Co doping on the microstructure, dielectric, and energy storage properties of ceramics were studied. The results show that Co is doped into the B site and does not cause an obvious change in ceramic phase structure. After doping cobalt, the grain size decreases obviously, and the sample becomes more uniform. At room temperature, the resistance value of BCZT–0.04Co is higher than that of other doped samples. The samples doped with Co transform into relaxor ferroelectrics, and the more obvious dispersion phase transition is observed. At the same time, the slim hysteresis loop is observed, and the energy storage loss is obviously reduced, lending to the improved energy storage efficiency. BCZT–0.04Co shows the highest dielectric constant at room temperature. Under the applied electric field of 84 kV/cm, the Wrec\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathrm{W}}_{\mathrm{rec}}$$\end{document} of BCZT–0.04Co ceramics is 0.42 J/cm3, the Wloss\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${W}_{\mathrm{loss}}$$\end{document} is reduced to 0.17 J/cm3, and the η\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\eta$$\end{document} is 71.2%.