Magnetocaloric effect in Gd1-xCexNi (x = 0–0.6): A cost-effective approach to tuning Curie temperature from 70 K to 30 K

Abstract

Magnetic refrigeration is a promising alternative to traditional gas compression refrigeration technologies, as it offers significantly higher energy efficiency. One factor hindering the widespread implementation of magnetic refrigeration is the dependence on expensive and critical rare earth elements needed to produce a strong magnetocaloric effect. Inside this work we explore substituting a non-critical rare earth element, Ce, into an established magnetocaloric material of choice, GdNi. Structural characteristics are investigated via x-ray powder diffraction, and the magnetocaloric effect is evaluated indirectly from heat capacity measurements as well as calculated using the mean field method. Our results show that small substitutions of Ce into GdNi results in the dilution of the magnetocaloric effect while maintaining relative cost effectiveness for small substitutions of Ce. As Ce content is increased, the cost effectiveness of the adiabatic temperature change (ΔTad) increases as high as 20% for (Gd0.4Ce0.6)Ni while the magnetic entropy change (-ΔSm) shows minimal improvement in cost effectiveness, falling from 3.93 J/kg*K in GdNi to 1.75 J/kg*K in (Gd0.4Ce0.6)Ni at 1 T applied field. This demonstrates that using Ce substitutions can be a powerful tool in both tuning Curie temperature and mitigating the reliance on critical elements as we look to develop towards a more sustainable future.