The calorimetric method of evaluating the performance of magnetocaloric materials

Recent progress in organometallic porphyrin‐based molecular materials for optical sensing, light conversion, and magnetic cooling

“…All results were obtained by a microcalorimetry method described in the works. [165,166] That is the direct method of MCE determination, in which adiabaticity of magnetization is maintained by rapid changes of a magnetic field. MCE related to the completely thermostatic calorimetric cell with solid paramagnets and water above it were observed in the first works.…”

Magnetocaloric Effect in Carbon-Containing Compounds

“…It was shown that, like 3D nanoparticles of metal oxides and hybrid composites of magnetic nanoparticles with graphene, singlemolecule magnets have a large and even giant MCE. For the first time, the magentocaloric behaviour of such molecular materials was determined by a direct method on an original [28] microcalorimetric apparatus and the first data about the interconnection between the chemical structure of their molecules and magnetothermal properties were obtained.…”

“…The measurements of MCE and heat capacity of the complexes of metalloporphyrins/metal phthalocyanines were made on an automated microcalorimetric unit with an isothermal shell [28]. The microcalorimetric measurement cell with a solid magnetic sample filled to the full volume with water together with the isothermal shell were placed into the pole gap (60 mm) of an electromagnet, which allowed determining the values of MCE and specific heat capacity in magnetic fields of 0 -1.0 T at temperatures of 278-343 K. Adiabatic magnetization was achieved by quickly varying the magnetic field.…”

“…To achieve this, the authors directly determined the thermodynamic parameters of MCE and specific heat capacity of [60] fullerene (С 60 ), 1'-N-methyl-2'-(pyridine-4-yl) pyrrolidino[3′,4′:1,2][60]fullerene (PyC 60 ), 5,10,15,20-(tetra-4-tret-butylphenyl)21H, 23H-porphynato)cobalt(II) (Co II TBPP) and the triad (PyC 60 ) 2 Co II TBPP. The MCE and specific heat capacity were obtained by the original microcalorimetric method [28] and by the method of differential scanning calorimetry (DSC), respectively. As a result, it was shown that the precursors under study and the triad demonstrated a positive magnetocaloric effect at room temperature when the magnetic induction changed from zero to 1.0 T.…”

“…By determining the thermodynamic parameters of MCE and specific heat capacity for the donoracceptor triad in comparison with the fullerene С 60 and precursors directly by the microcalorimetric method developed by us [28] and by the DSC, respectively, we have shown that carbon nanoforms C 60 , PyC 60 , porphyrin complex and the triad have positive MCE values of 0.004, 0.016, 0.028 and 0.007 K, respectively, at 278 K and magnetic field induction of 1.0 T (Fig. 13).…”