Structural, magnetic and magnetocaloric properties in distorted RE <sub>2</sub>NiTiO<sub>6</sub> double perovskite compounds
Zhenqian Zhang, Peng Xu, Youshun Jia, Lingwei Li
Abstract
Abstract The magnetocaloric effect based Magnetic refrigeration (MR) was considered a novel energy-efficient and environmentally benign cooling method. However, the lack of suitable magnetic solids has slowed the development of its practical applications. We herein fabricated the RE 2 NiTiO 6 ( RE = Gd, Tb and Ho) double perovskite (DP) compounds and systematically determined their structural, magnetic and magnetocaloric properties by experimental determination and density functional theory calculations, in which the Gd 2 NiTiO 6 was realized to exhibit promising cryogenic magnetocaloric performances. The results indicated that all the RE 2 NiTiO 6 DP compounds crystallized in a distorted monoclinic structure with P 2 1 / n space group and underwent a second order type magnetic phase transition around 4.3, 4.5 and 3.9 K, for Gd 2 NiTiO 6 , Tb 2 NiTiO 6 and Ho 2 NiTiO 6 , respectively. The magnetocaloric performances were checked by the parameters of maximum magnetic entropy change and relative cooling power, which are 31.28 J·kg −1 ·K −1 and 242.11 J·kg −1 for Gd 2 NiTiO 6 , 13.08 J·kg −1 ·K −1 and 213.41 J·kg −1 for Tb 2 NiTiO 6 , 11.98 J·kg −1 ·K −1 and 221.73 J·kg −1 for Ho 2 NiTiO 6 under the magnetic field change of 0–50 kOe, respectively. Evidently, the Gd 2 NiTiO 6 compound exhibit promising magnetocaloric performances and therefore is of potential for practical cryogenic MR applications.