Gadolinium sulfate modified by formate to obtain optimized magneto-caloric effect

Area of Science:

• Inorganic Chemistry
• Materials Science
• Magnetism

Background:

• Gadolinium(III) based coordination polymers are investigated for their magnetic properties.
• The magneto-caloric effect (MCE) is a key property for magnetic refrigeration technologies.
• Tailoring ligand environments in coordination polymers can tune magnetic behavior.

Purpose of the Study:

• To synthesize novel gadolinium(III) coordination polymers.
• To investigate the effect of varying synthesis conditions on structural and magnetic properties.
• To evaluate the magneto-caloric effect of the synthesized materials.

Main Methods:

• Solvothermal synthesis of coordination polymers using gadolinium sulfate.
• Structural characterization through X-ray diffraction.
• Magnetic property measurements, including magnetic entropy change calculations.

Main Results:

• Three new Gd(III) coordination polymers were successfully synthesized: [Gd2(C2H6SO)(SO4)3(H2O)2]n (1), {[Gd4(HCOO)2(SO4)5(H2O)6]·H2O}n (2), and [Gd(HCOO)(SO4)(H2O)]n (3).
• Increasing the ratio of formic acid (HCOOH) and dimethyl sulfoxide (DMSO) led to formate coordination, increased sulfate coordination numbers, and decreased water/DMSO content.
• Spin densities and magneto-caloric effect (MCE) were enhanced with increasing formate content.

Conclusions:

• The incorporation of formate anions positively influences the MCE performance of gadolinium coordination polymers.
• Complex 3 demonstrated the highest magnetic entropy change (-ΔSm = 49.91 J kg(-1) K(-1)) at 2 K and 7 T.
• These findings highlight the potential of rationally designed coordination polymers for advanced magnetic cooling applications.