Large Magnetocaloric Effect in Li3K9Gd3(BO3)7 Crystal Featuring Sandwich-Like Three-Dimensional Framework

Wang Liu; Fei Liang; Yuwei Chen; Huimin Song; Jingcheng Feng; Jun Shen; Zheshuai Lin; Heng Tu; Guochun Zhang

doi:10.1021/acs.inorgchem.1c00633

Large Magnetocaloric Effect in Li₃K₉Gd₃(BO₃)₇ Crystal Featuring Sandwich-Like Three-Dimensional Framework

Inorg Chem. 2021 May 3;60(9):6796-6803. doi: 10.1021/acs.inorgchem.1c00633. Epub 2021 Apr 12.

Authors

Wang Liu^{1

2}, Fei Liang^{1

3}, Yuwei Chen^{1

2}, Huimin Song^{1

2}, Jingcheng Feng^{1

2}, Jun Shen⁴, Zheshuai Lin¹, Heng Tu^{1

2}, Guochun Zhang^{1

3

2}

Affiliations

¹ Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
² Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
³ State Key Laboratory of Crystal Materials and Institute of Crystal Materials, Shandong University, Jinan 250100, People's Republic of China.
⁴ Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.

PMID: 33843230
DOI: 10.1021/acs.inorgchem.1c00633

Abstract

A new Gd-based borate crystal, Li₃K₉Gd₃(BO₃)₇, has been successfully obtained via the high-temperature solution method using Li₂O-K₂O-B₂O₃ self-flux. It crystallizes in monoclinic space group P2/n (no. 10) with lattice parameters a = 11.3454(6) Å, b = 9.9881(4) Å, c = 11.4467(7) Å, α = γ = 90 ^o, β = 114.782(7) ^o, and Z = 2. Li₃K₉Gd₃(BO₃)₇ exhibits an intriguing sandwich-like three-dimensional (3D) framework constructed from [Gd-B-O]_∞ layers, KO_n (n = 6 and 8) polyhedra, and LiO₄ tetrahedra, in which [Gd-B-O]_∞ layers are built from two types of GdO₈ polyhedra and triangular BO₃ units. Magnetic measurements showed that Li₃K₉Gd₃(BO₃)₇ exhibits a large magnetocaloric effect with -ΔS_m = 39.3 J kg^-1 K^-1 at 2.0 K for ΔH = 7 T, which is slightly higher than that of the commercial gadolinium gallium garnet under the same conditions. The powder X-ray diffraction, infrared spectrum, and UV-vis-NIR diffuse reflectance spectrum were also performed to characterize Li₃K₉Gd₃(BO₃)₇. The electronic band structures, partial density of states, and refractive indices of Li₃K₉Gd₃(BO₃)₇ were investigated via the first-principle calculations.