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Chemical substitution is an effective method for tailoring the electrical and magnetic properties of functional materials. In this work, (1–x)Ba 0.1 Sr 0.9 TiO 3 - xBiFeO 3 (0.2  ≤ x  ≤ 0.8) ceramics were prepared by the modified Pechini method. X-ray diffraction patterns manifest that the samples undergo a gradual structural transformation from rhombohedral phase to tetragonal phase with increasing the content of Ba 0.1 Sr 0.9 TiO 3 (BST). Dielectric properties show that T C can be modulated by the doping level of BST in a wide range from 885 K to 260 K accompanied by the ferroelectric transformation from non-relaxor type to relaxor type ferroelectricity. The room temperature ferroelectricity, ferromagnetism and intrinsic magnetodielectric are observed in the BiFeO 3 -rich samples. Magnetization and magnetodielectric measurement both show that the spin cycloid is destroyed by the substitution of BST and the critical field for the transition from spiral to antiferromagnetic collinear magnetic structure decreases with increasing the amount of BST. These findings manifest that this materials are quite promising for potential applications in BFO-based magnetoelectric devices and electrocaloric cooling technologies. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we have succeeded in destabilizing LiBH4 by the addition of SrH2, via the reaction 6LiBH4 +SrH2 →SrB6 +6LiH+10H2 with a theoretical hydrogen capacity of 9.1wt.%. According to the van’t Hoff and Arrhenius equations, the dehydrogenation enthalpy change and activation energy for the LiBH4/SrH2 system were experimentally determined to be 48kJ/mol H2 and 64kJ/mol, respectively. Both are remarkably reduced in comparison with the pristine LiBH4, which is responsible for the improved dehydrogenation property of the LiBH4/SrH2 system. The dehydrogenated products SrB6 +6LiH can be rehydrogenated to form LiBH4 and LiSrH3 at 723K under an initial hydrogen pressure of 8.0MPa. [Copyright &y& Elsevier]

The effects of Co doping on structural, dielectric, and magnetic properties of multiferroic 0.6BiFe 1- x Co x O 3 -0.4(Bi 0.5 K 0.5 )TiO 3 (0 ≤ x ≤ 0.2) ceramics have been investigated. The samples undergo a structural transition from pseudocubic to rhombohedral phase at x = 0.1. The maximum remnant polarization of 57.8 μC/cm 2 and remnant magnetization of 0.107 emu/g are observed in the x = 0.15 sample. The ferromagnetism is proposed to originate from the suppression of spiral spin structure with the canting of the antiferromagnetically ordered spins caused by the substitution of Co for Fe ions. Moreover, the magnetodielectric effect can be observed in the x = 0.15 sample. [ABSTRACT FROM AUTHOR]