Barium zirconate titanate[Ba(ZrxTi_(1−x))O_(3)]solid solutions are promising lead-free ferroelectric materials that have received substantial interest.Thermodynamic analysis based on phenomenological Landau–Devonshir...Barium zirconate titanate[Ba(ZrxTi_(1−x))O_(3)]solid solutions are promising lead-free ferroelectric materials that have received substantial interest.Thermodynamic analysis based on phenomenological Landau–Devonshire theory is a powerful method for theoretical investigation of ferroelectric materials,but cannot be applied to Ba(ZrxTi1−x)O3 because there is no thermodynamic potential.In this paper,a thermodynamic potential for Ba(ZrxTi_(1−x))O_(3)(0≤x≤0.3)solid solutions is constructed,and then a thermodynamic analysis carried out.The results accurately reproduce known phase structures and their transition temperatures,with good agreement with experimentally measured polarization,dielectric,and piezoelectric constants.It is found that Ba(ZrxTi_(1−x))O_(3) solid solutions at room temperature have three phase boundaries,including a tetragonal–orthorhombic phase boundary at x=0.013,an orthorhombic–rhombohedral phase boundary at x=0.0798,and a rhombohedral–paraelectric phase boundary at x=0.2135.The results also indicate that the chemical composition-induced ferroelectric–paraelectric phase boundary has superior electromechanical properties,suggesting a new way to enhance electromechanical coupling in Ba(ZrxTi_(1−x))O_(3) solid solutions.展开更多
基金This work was partially supported by the National Key Research and Development Program of China(2016YFA0201001)NSFC(Approval Nos.11572276,11772286,11502225,11627801,and 11402221)+2 种基金Project supported by Hunan Provincial Natural Science Foundation of China(2017JJ3312 and 2016JJ6146)Scientific Research Fund of Hunan Provincial Education Department(16A202 and 17B251)Hunan Provincial Innovation Foundation for Postgraduate(CX2017B279).
文摘Barium zirconate titanate[Ba(ZrxTi_(1−x))O_(3)]solid solutions are promising lead-free ferroelectric materials that have received substantial interest.Thermodynamic analysis based on phenomenological Landau–Devonshire theory is a powerful method for theoretical investigation of ferroelectric materials,but cannot be applied to Ba(ZrxTi1−x)O3 because there is no thermodynamic potential.In this paper,a thermodynamic potential for Ba(ZrxTi_(1−x))O_(3)(0≤x≤0.3)solid solutions is constructed,and then a thermodynamic analysis carried out.The results accurately reproduce known phase structures and their transition temperatures,with good agreement with experimentally measured polarization,dielectric,and piezoelectric constants.It is found that Ba(ZrxTi_(1−x))O_(3) solid solutions at room temperature have three phase boundaries,including a tetragonal–orthorhombic phase boundary at x=0.013,an orthorhombic–rhombohedral phase boundary at x=0.0798,and a rhombohedral–paraelectric phase boundary at x=0.2135.The results also indicate that the chemical composition-induced ferroelectric–paraelectric phase boundary has superior electromechanical properties,suggesting a new way to enhance electromechanical coupling in Ba(ZrxTi_(1−x))O_(3) solid solutions.
