具有Ruddlesden-Popper结构的杂化非本征铁电体(Ca_(1-x)Sm_(x))_(3)Ti_(2)O_(7)陶瓷的制备及其物理性能

Preparation and physical properties of improper ferroelectric(Ca_(1-x)Sm_(x))_(3)Ti_(2)O_(7) ceramics with Ruddlesden-Popper structure

为探究稀土离子掺杂对Ca_(3)Ti_(2)O_(7)物理性能的调控,采用固相反应法制备了Sm^(3+)掺杂的(Ca_(1-x)Sm_(x))_(3)Ti_(2)O_(7)(x=0,0.02,0.04)陶瓷样品,通过XRD、XPS、紫外-可见光吸收光谱以及第一性原理计算等方法对样品的晶体结构、光学性能、电学性能和磁学性能进行分析.结果表明:随着Sm^(3+)含量的增加,(Ca_(1-x)Sm_(x))_(3)Ti_(2)O_(7)的晶胞参数逐渐增大.Sm^(3+)掺杂导致氧空位减少,因此样品的漏电流随着Sm^(3+)掺杂量的增加而减小.同时,随着Sm^(3+)掺杂量的增加,样品的光学带隙呈现增大趋势.此外,第一性原理研究表明,Sm^(3+)掺杂可在体系中诱导出磁性能,进一步丰富了该材料的物理性能.

In order to investigate the influence of rare earth ion doping on the physical properties of Ca_(3)Ti_(2)O_(7),the ceramic sam-ples of Sm^(3+)ion-doped(Ca_(1-x)Sm_(x))_(3)Ti_(2)O_(7)(x=0,0.02,0.04)were prepared by solid-state reaction method.The crystal structure,optical properties,electrical properties and magnetic properties of the samples were analyzed by X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),UV-VIS absorption spectroscopy and first-principles calculations.The experimental results show that with the increase of Sm^(3+)ion content,the unit cell parameters of(Ca_(1-x)Sm_(x))3Ti2O7 gradually increase.The leakage cur-rent of the samples decreases with the increase of Sm^(3+)doping because Sm^(3+)doping led to a reduction in oxygen vacancy content.Additionally,the optical bandgap of the samples exhibits an increasing trend with the growing concentration of Sm^(3+)ions.In addition,first-principles studies indicate that Sm^(3+)doping can induce magnetic properties in the system,further enriching the physical properties of the material.