In this study, we investigate the magnetic and magnetocaloric properties of Cr-based spinel sulphides Fe1-xCuxCr2S4 (x = 0.0 and x = 0.5). The magnetic transition temperature of FeCr2S4 (176 K) increases to 330 K when 50% of Fe in FeCr2S4 structure is substituted with Cu.

Temperature-dependent Zero-Field-Cooled (ZFC) and Field-Cooled (FC) magnetic moment measurements show a paramagnetic (PM) to ferrimagnetic (FiM) phase transition in our samples. Magnetocaloric properties were investigated through magnetization isotherm measurements. The maximum magnetic entropy change values are -2.78 J/Kg. K and -2.11 J/Kg. K under 5 T magnetic field, for x = 0 and x = 0.5 in Fe1-xCuxCr2S4, respectively. Analysis of phenomenological universal curves and Arrott plots indicate a second-order magnetic transition for both compounds. Consequently, Fe0.5Cu0.5Cr2S4 emerges as a promising candidate for magnetic refrigeration applications due to its considerable high magnetic entropy change and its proximity to room temperature transition.