Vinnik Denis A, Zhivulin Vladimir E, Trofimov Evgeny A, Gudkova Svetlana A, Punda Alexander Yu, Valiulina Azalia N, Gavrilyak Maksim, Zaitseva Olga V, Taskaev Sergey V, Khandaker Mayeen Uddin, Alqahtani Amal, Bradley David A, Sayyed M I, Turchenko Vitaliy A, Trukhanov Alex V, Trukhanov Sergei V
Laboratory of Single Crystal Growth, South Ural State University, 76, Lenin Av., 454080 Chelyabinsk, Russia.
Centre for Applied Physics and Radiation Technologies, School of Engineering and Technology, Sunway University, Bandar Sunway 47500, Selangor, Malaysia.
Nanomaterials (Basel). 2021 Dec 23;12(1):36. doi: 10.3390/nano12010036.
Three high-entropy Sm(Eu,Gd)CrMnFeCoNiO perovskite solid solutions were synthesized using the usual ceramic technology. The XRD investigation at room temperature established a single-phase perovskite product. The Rietveld refinement with the FullProf computer program in the frame of the orthorhombic Pnma (No 62) space group was realized. Along with a decrease in the V unit cell volume from ~224.33 Å for the Sm-based sample down to ~221.52 Å for the Gd-based sample, an opposite tendency was observed for the unit cell parameters as the ordinal number of the rare-earth cation increased. The average grain size was in the range of 5-8 μm. Field magnetization was measured up to 30 kOe at 50 K and 300 K. The law of approach to saturation was used to determine the M spontaneous magnetization that nonlinearly increased from ~1.89 emu/g (Sm) up to ~17.49 emu/g (Gd) and from ~0.59 emu/g (Sm) up to ~3.16 emu/g (Gd) at 50 K and 300 K, respectively. The M residual magnetization and H coercive force were also determined, while the SQR loop squareness, k magnetic crystallographic anisotropy coefficient, and H anisotropy field were calculated. Temperature magnetization was measured in a field of 30 kOe. ZFC and FC magnetization curves were fixed in a field of 100 Oe. It was discovered that the T magnetic ordering temperature downward-curve decreased from ~137.98 K (Sm) down to ~133.99 K (Gd). The spin glass state with ferromagnetic nanoinclusions for all the samples was observed. The
采用常规陶瓷工艺合成了三种高熵Sm(Eu,Gd)CrMnFeCoNiO钙钛矿固溶体。室温下的XRD研究确定产物为单相钙钛矿。在正交Pnma(编号62)空间群框架下,使用FullProf计算机程序进行了Rietveld精修。随着晶胞体积V从Sm基样品的约224.33 Å减小到Gd基样品的约221.52 Å,随着稀土阳离子序数增加,晶胞参数呈现相反趋势。平均晶粒尺寸在5 - 8 μm范围内。在50 K和300 K下测量了高达30 kOe的场磁化强度。利用趋近饱和定律确定自发磁化强度M,在50 K和300 K时,M分别从约1.89 emu/g(Sm)非线性增加到约17.49 emu/g(Gd)以及从约0.59 emu/g(Sm)增加到约3.16 emu/g(Gd)。还确定了剩余磁化强度M和矫顽力H,同时计算了SQR回线矩形度、磁晶各向异性系数k和各向异性场H。在30 kOe场中测量了温度磁化强度。在100 Oe场中固定了零场冷却(ZFC)和场冷却(FC)磁化曲线。发现磁有序温度T的下降曲线从约137.98 K(Sm)降至约133.99 K(Gd)。观察到所有样品均具有含铁磁纳米夹杂物的自旋玻璃态。计算了铁磁纳米夹杂物的平均