A thermomagnetic analysis of an eco-friendly nano-sized dysprosia for energy efficient cryo-cooling systems

A substantial share of overall energy consumption in developing countries accounts for refrigeration systems and heating/air conditioning equipment. The direct emission of carbon dioxide into the atmosphere is due to the release of refrigerants with a high global warming capacity. The efficiency of transition metal-doped nano-sized dysprosia (NSD) as a magnetic refrigerant is studied in this work. The NSD and transition-doped NSD were synthesised using the sol–gel process. Special precautions were taken to capture the toxic gases evolved from the reaction chamber during the synthetic process, thereby eliminating the environmental impact. The structural and surface morphological studies of materials revealed that the particles are spherical in shape with a body-centred cubic structure (Ia-3). The chemical analysis of materials confirms the presence of transition metal ions, which play a major role in the structural distortion of doped NSDs. The magnetic studies of NSDs revealed that antiferromagnetic and ferromagnetic properties exhibited predominantly at low temperature, whereas at high-temperature, paramagnetic properties are observed. It was also found that the magnetic entropy change of NSDs at the applied magnetic field is comparatively higher, making them a suitable material for eco-friendly cryogenic systems. Graphical abstract