| Abstract Scope |
The impacts of local chemical order (LCO) on the physical properties of high-entropy alloys (HEAs) have been widely discussed. However, it is still unclear whether the LCO extends to HEA surfaces, which may impact the surface-based properties, such as corrosion, oxidation, and catalytic activities. In this talk, through the utilization of scanning tunneling microscopy (STM), two surface LCO domains with corresponding quasi-long-range orderings (QLRO) are directly observed on a CoCrFeMnNi surface. In combination with density functional theory (DFT) calculations, the LCO in the QLRO supercell is determined. The findings provide evidence of the existence of surface LCO and demonstrate a method to directly observe the surface LCO. This work paves the road towards correlating the LCO to the material properties, which facilitates the design of HEAs with desirable properties. |