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Constructing composite structure is an effective way to improve dielectric energy storage properties. However, ionic diffusion between composite members is generally inevitable, which mixes the effects of solid solution with composite structure on property to some extent. To exclude the ionic diffusion effect as much as possible, antiferroelectric (Pb0.97La0.02)(Zr0.5Sn0.4Ti0.1)O3 (PLZST) was sintered at a relatively high temperature to precipitate SnO2 particles, then more SnO2 were introduced to from (1-x)PLZST:xSnO2 (x = 0–0.25) composite. The results showed that composite structure had significant effects on microstructures and properties with changed lattice parameter, decreased grain size, increased Curie temperature, suppressed antiferroelectric property, and enhanced electric breakdown strength. The optimal composition of x = 0.2 showed high energy storage density of 2.38 J/cm3. This work provides a robust platform to investigate the effect of composite microstructure on electrical properties, which is helpful for further developing high performance composite materials.

Two new intermetallic compounds RCo(3)Si(4) (R = Pr, Nd) with tetragonal NaZn13-derivative structure have been synthesized. Their crystal structures have been determined by X-ray powder diffraction and refined by the Rietveld technique. The space group for the tetragonal structure is 14/mcm. The lattice parameters are a = 7.789(1) Angstrom, c = 11.509(2) Angstrom and a = 7.791(2) Angstrom, c = 11.516(3) Angstrom for PrCo3Si4, and NdCo3,Si, respectively. The Si atoms strongly prefer to occupy the crystallographic 161(2) position.

By means of X-ray diffraction analysis, it is shown for x < 0.4 that all the interstitial Sm-2(Fe1-xAlx)(17)N-y nitrides and the parent compounds crystallize with Th2Zn(17)-type structure. The lattice constants of the parent compounds increase linearly with Al concentration. The introduction of nitrogen atoms leads to a further increase in the lattice constants, but the increase becomes smaller with increasing Al concentration; this can be related to the fact that the nitrogen content introduced into the parent compounds decreases nearly linearly with increasing Al concentration. The dependence on composition of T-c of the parent compounds exhibits a maximum, whereas T-c of the nitrides decreases monotonically with Al content from 750 K for x=0 to 313 K for x=0.4. The introduction of nitrogen leads to enhancement of the average magnetic moment of Fe in Sm2Fe17, whereas the substitution of Al for Fe leads to a decrease in the average magnetic moment of Fe in both the nitrides and the parent compounds. The anisotropy field B-a of nitrides is almost independent of the Al concentration for x less than or equal to 0.3, then decreases very fast and becomes zero at about x = 0.4.

CeCuSn, which forms in the hexagonal CaIn 2 -type of structure, orders antiferromagnetically at 8.6 K. A second maximum at about 7.35 K seen in the temperature dependence of the specific heat indicates a rearrangement of the antiferromagnetic structure. The antiferromagnetic ordering is also reflected in the temperature dependence of the electrical resistivity. Upon application of magnetic fields up to 5 T, a complex development of magnetic phases can be followed by monitoring the temperature dependencies of the magnetization and the specific heat. In the B-T diagram, three different magnetic phases were detected and their boundaries could be determined.

Mossbauer spectroscopy was used to study the substitution effect of Y for Sm atoms and the occupation of N atoms in (Sm 1—x Y x ) 2 Fe 17 N y ( x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0; 2 y e sites but also 3 b sites. The experimental results have confirmed the following facts. (1) The crystal structure changes when x exceeds 0.5. (2) The average magnetic hyperfine fields at the different iron sites in (Sm 1—x Y x ) 2 Fe 17 N y vary with the yttrium concentration. (c) (Sm 1—x Y x ) 2 Fe 17 N y compounds display an easy c axis anisotropy as the yttrium content ranges from x = 0 to 0.8 according to the Mossbauer fitting results.

Lattice constants, high field magnetic isotherms at 4.2 K 1 Curie temperatures and spin reorientation temperatures are reported for RFe 10 Cr 2 compounds with R ≈ Y, Gd, Tb, Dy, Ho, Er, Tm, Lu. The value of the rare earth-transition metal (T) magnetic coupling constant J RT / k derived by a mean field analysis of the Curie temperatures is about − 15 K. This value is larger than the value of about −9 K obtained in a mean field analysis of the effect of the departure of the perfect collinear ferrimagnetic orientation of the sublattice magnetizations occurring in high magnetic fields. A tentative spin phase diagram for the RFe 10 Cr 2 series is presented.