Recent advances in the synthesis and fabrication methods of high-entropy alloy nanoparticles

High-entropy alloy nanoparticles (HEA NPs) containing four or more elements possess several advantages over traditional alloy nanoparticles (NPs), such as higher strength, greater thermal stability, enhanced oxidation resistance, stronger catalytic activity, and greater flexibility in adjusting element composition and composition ratio. However, the development of HEA NPs has been limited by preparation difficulties caused by the challenge of achieving complete miscibility between multiple-component elements and the unique high-entropy states. In this review, we provide a comprehensive summary of recent breakthroughs in synthesizing and fabricating HEA NPs. We describe the experimental procedures and principles of various synthesis methods, including furnace pyrolysis, carbothermal shock (CTS) method, pulse laser, solvothermal method, microwave heating, hydrogen spillover-driven, sputtering deposition, annealing on mesoporous materials, arc discharge methods and using liquid metal. Additionally, we delve into recent improvements made to some of these methods or novel NPs synthesized using them. Finally, we review the current applications of HEA NPs and provide insights into potential applications of this rapidly emerging research field.