Magnetocaloric Effect and Thermal Conductivity of a 3D Coordination Polymer of [Gd(HCOO)(C₂O₄)]_n

Abstract

A 3D coordination polymer, [Gd(HCOO)(C 2 O 4 )] n was prepared. Its magnetocaloric effect (MCE) (32.7 J K −1 kg −1 at 2 K and 2 T) is significantly larger than that of commercial Gd 3 Ga 5 O 12 (GGG) (14.6 J kg −1 K −1 at 2 K and 2 T), while its thermal conductivity (9.9 W m −1 K −1 at 3 K) is comparable to that of the commercial GGG (about 10 W m −1 K −1 at 3 K).

Gd(iii)-Based inorganic polymers, metal–organic frameworks and coordination polymers for magnetic refrigeration

“…3a). 15 Complex 10 exhibited weak magnetic exchange coupling and the MCE was up to 58.9 J kg −1 K −1 at 7 T and 2 K (32.7 J kg −1 K −1 at 2 T and 2 K) (Fig. 3b).…”

“…[11][12][13][14] Therefore, Gd(III)-based inorganic polymers, MOFs, and CPs with possible large magnetic and physical densities as well as weak magnetic interactions have received much attention from researchers. [15][16][17] To obtain Gd(III)-based inorganic polymers, MOFs, and CPs with a large ΔS m under low fields, a key point is to choose suitable Gd III -ion sources and ligands. 18,19 Gd III salts, including Gd(NO 3 ) 3 , GdCl 3 , Gd 2 (SO 4 ) 3 , GdPO 4 , and Gd 2 (CO 3 ) 3 , are the most common Gd III -ion sources because of their relatively good solubility in common solvents.…”

“…11–14 Therefore, Gd( iii )-based inorganic polymers, MOFs, and CPs with possible large magnetic and physical densities as well as weak magnetic interactions have received much attention from researchers. 15–17…”

“…Fig. 3 (a) View of the 3D structure of 10 along the c axis; (b) temperature dependence of −ΔS m for selected ΔH values obtained from magnetization measurements 15. …”

Gd(OH)F2: A Promising Cryogenic Magnetic Refrigerant

“…To obtain the magnetic refrigerants with a large MCE in a wide temperature range and low T o in the sub-kelvin temperature region, various Gd-based materials, such as molecule-based clusters, − inorganic salts, − inorganic metallic oxides, − and coordination polymers, − were selected as magnetic refrigerants in the past decades. Although some large MCE magnetic refrigerants, such as Gd­(HCOO) 3 , Gd­(OH) 3 , GdPO 4 , Gd­(OH)­CO 3 , and GdF 3 , have been successfully obtained, on the one hand, their MCE remains not large enough, in addition to GdF 3 ; especially, their T o is only comparable to that of GGG (0.8 K), while the T o in GdF 3 is up to 1.25 K. Therefore, it remains a great challenge to obtain the magnetic refrigerants with a large MCE in a wide temperature range and low T o in the sub-kelvin temperature region.…”