{Gd22Ni22}: A double-shell nanocluster exhibits large magnetocaloric effect

Abstract

Atomically well-defined metal nanoscale clusters have attracted significant interest owing to their fascinating structures and wide potential applications. The Gd (III) containing clusters, in particular, attract great research attention due to their potential magnetic refrigeration applications. Here, we report the synthesis of a gigantic double-shell 3d-Gd cluster, {Gd22Ni22}, which is composed of [Gd5Ni2(μ2-OH)4(μ2-OH)6]9+ and [Gd6Ni9(μ2-OH)20(μ3-OH)10]6+ structural units. Magnetic characterization reveals that the {Gd22Ni22} cluster exhibits a large magnetocaloric effect (MCE), with an isothermal magnetic entropy change of 46.0 J kg−1 K−1 at 2.0 K for ΔH = 7 T, which is one of the largest among all the high-nuclearity Ni–Gd clusters. The large magnetic entropy change of {Gd22Ni22} cluster is closely related to its weak magnetic interaction.