“…RC can be defined as the product of the maximum value of the peak of the magnetic entropy change and the width of ∆S M peak at its half-height [1]. In addition, nanostructuring can enhance the field dependence of the magnetocaloric effect [11,14,17,18]. Moreover, appropriate annealing of polycrystalline materials can, to some extent, restore the perfection of their crystal structure (due to the stress relaxation, movement of the vacancies, etc.)…”