posted on 2022-12-20, 13:33authored byNils Lau
Nyborg Broge, Andreas Dueholm Bertelsen, Frederik Søndergaard-Pedersen, Bo Brummerstedt Iversen
High-entropy alloys (HEAs) present a promising class
of materials
due to extraordinary properties and vast possibilities for tailoring
product characteristics through changes in stoichiometry. Nanosized
HEAs are especially interesting with respect to catalysis of multistep
reactions and replacement of scarce, expensive, and/or toxic elements.
Finding suitable methods for the synthesis of nano-HEAs remains a
severe challenge, and typical methods are limited in productivity,
compatibility of different elements, substrate types, and/or specialized
laboratory equipment. Here, we report a simple solvothermal method
for the synthesis of eight-component Pt–Ir–Pd–Rh–Ru–Cu–Ni–Co
HEA nanoparticles with a high potential production capacity. The method
relies on simple autoclaves heated to a moderate temperature. In situ
X-ray scattering experiments show that the individual metal components
form from one-element precursors at higher reaction temperatures,
suggesting that the formation is auto-catalyzed, that is, the particles
catalyze their own growth, in correspondence with previous findings
for a five element (Pt–Ir–Rh–Pd–Ru) noble-metal
HEA. This paper extends the method to cheaper and more abundant 3d
metals (Co, Ni, and Cu) despite the differences in atomic radii and
chemical reactivity and thereby adds significantly to the synthetic
chemistry and understanding of HEA nanomaterials.