Mesoporous high-entropy PtPdRhCuIrSe particles via a soft-chemical approach using a reducing agent

Abstract The development of high-entropy materials (HEMs) has garnered significant attention due to their exceptional properties and advantages. However, the structural complexity of multielement systems makes controlling their nanoscale morphology a big challenge. We successfully synthesized metallic mesoporous HEMs containing Pt-group metals of Pt, Pd, Rh, and Ru [Nat. Commun. 2023, 14 (1): 4182]. However, the synthesis of mesoporous HEMs with more metal elements, such as Ir, remains challenging. In this work, a simple wet-chemical reduction method is employed to synthesize new porous HEMs. Upon the reduction process control, the metal and Se ions are reduced and aggregated, while the polymeric micelles introduce the porous structures. It is found that the Ir content in HEM increases with the proportion of Se, leading to higher mixing entropy. This approach achieves enhanced entropy and compositional control of mesoporous metals.