Structural, magnetic and magnetocaloric properties in distorted RE 2NiTiO6 double perovskite compounds

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 2NiTiO6 (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 Gd2NiTiO6 was realized to exhibit promising cryogenic magnetocaloric performances. The results indicated that all the RE 2NiTiO6 DP compounds crystallized in a distorted monoclinic structure with P2(1)/n space group and underwent a second order type magnetic phase transition around 4.3, 4.5 and 3.9 K, for Gd2NiTiO6, Tb2NiTiO6 and Ho2NiTiO6, respectively. The magnetocaloric performances were checked by the parameters of maximum magnetic entropy change and relative cooling power, which are 31.28 J center dot kg(-1)center dot K-1 and 242.11 J center dot kg(-1) for Gd2NiTiO6, 13.08 J center dot kg(-1)center dot K-1 and 213.41 J center dot kg(-1) for Tb2NiTiO6, 11.98 J center dot kg(-1)center dot K-1 and 221.73 J center dot kg(-1) for Ho2NiTiO6 under the magnetic field change of 0-50 kOe, respectively. Evidently, the Gd2NiTiO6 compound exhibit promising magnetocaloric performances and therefore is of potential for practical cryogenic MR applications.

Automated summary

The magnetocaloric effect based Magnetic refrigeration (MR) is a novel and environmentally friendly cooling method, but the lack of suitable magnetic solids has hindered its practical applications. In this study, we fabricated the RE2NiTiO6 (RE = Gd, Tb and Ho) double perovskite (DP) compounds and investigated their structural, magnetic and magnetocaloric properties. The Gd2NiTiO6 compound exhibited promising cryogenic magnetocaloric performances, suggesting its potential for practical MR applications.