A series of high-entropy ceramics with the nominal composition(Mg_(0.5)Zn_(0.5))_(0.4+x)Li_(0.4)(Ca_(0.5)Sr_(0.5))_(0.4−x)TiO_(3)(0≤x≤0.4)has been successfully synthesized using the conventional solid-phase method.T...A series of high-entropy ceramics with the nominal composition(Mg_(0.5)Zn_(0.5))_(0.4+x)Li_(0.4)(Ca_(0.5)Sr_(0.5))_(0.4−x)TiO_(3)(0≤x≤0.4)has been successfully synthesized using the conventional solid-phase method.The(Mg_(0.5)Zn_(0.5))_(0.4+x)Li_(0.4)(Ca_(0.5)Sr_(0.5))_(0.4−x)TiO_(3)ceramics are confirmed to be composed of the main phase(Zn,Mg,Li)TiO_(3)and the secondary phase Ca_(0.5)Sr_(0.5)TiO_(3)by X-ray diffractometer,Rietveld refinement,and X-ray spectroscopy analysis.The quality factor(Q×f)of the samples is inversely proportional to the content of the Ca_(0.5)Sr_(0.5)TiO_(3)phase,and it is influenced by the density.The secondary phase and molecular polarizability(α_(T))have a significant impact on the dielectric constant(ε_(r))of the samples.Moreover,the temperature coefficient of resonant frequency(τ_(f))of the samples is determined by the distortion of[TiO_(6)]octahedra and the secondary phase.The results indicate tha(Mg_(0.5)Zn_(0.5))_(0.4+x)Li_(0.4)(Ca_(0.5)Sr_(0.5))_(0.4−x)TiO_(3)ceramics achieve ideal microwave dielectric properties(ε_(r)=17.6,Q×f=40900 GHz,τ_(f)=-8.6 ppm/℃)when x=0.35.(Mg_(0.5)Zn_(0.5))_(0.4+x)Li_(0.4)(Ca_(0.5)Sr_(0.5))_(0.4−x)TiO_(3)ceramics possess the potential for application in wireless communication,and a new approach has been provided to enhance the perform-ance of microwave dielectric ceramics.展开更多
基金supported by the Sichuan Science and Technology Program,China(No.2023YFQ0082)the Guangdong Provincial Key Laboratory of Electronic Functional Materials and Device,China(No.EFMD2022005Z)the State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals,China(No.SKL-SPM-202021).
文摘A series of high-entropy ceramics with the nominal composition(Mg_(0.5)Zn_(0.5))_(0.4+x)Li_(0.4)(Ca_(0.5)Sr_(0.5))_(0.4−x)TiO_(3)(0≤x≤0.4)has been successfully synthesized using the conventional solid-phase method.The(Mg_(0.5)Zn_(0.5))_(0.4+x)Li_(0.4)(Ca_(0.5)Sr_(0.5))_(0.4−x)TiO_(3)ceramics are confirmed to be composed of the main phase(Zn,Mg,Li)TiO_(3)and the secondary phase Ca_(0.5)Sr_(0.5)TiO_(3)by X-ray diffractometer,Rietveld refinement,and X-ray spectroscopy analysis.The quality factor(Q×f)of the samples is inversely proportional to the content of the Ca_(0.5)Sr_(0.5)TiO_(3)phase,and it is influenced by the density.The secondary phase and molecular polarizability(α_(T))have a significant impact on the dielectric constant(ε_(r))of the samples.Moreover,the temperature coefficient of resonant frequency(τ_(f))of the samples is determined by the distortion of[TiO_(6)]octahedra and the secondary phase.The results indicate tha(Mg_(0.5)Zn_(0.5))_(0.4+x)Li_(0.4)(Ca_(0.5)Sr_(0.5))_(0.4−x)TiO_(3)ceramics achieve ideal microwave dielectric properties(ε_(r)=17.6,Q×f=40900 GHz,τ_(f)=-8.6 ppm/℃)when x=0.35.(Mg_(0.5)Zn_(0.5))_(0.4+x)Li_(0.4)(Ca_(0.5)Sr_(0.5))_(0.4−x)TiO_(3)ceramics possess the potential for application in wireless communication,and a new approach has been provided to enhance the perform-ance of microwave dielectric ceramics.
