Corrosion behavior of high-entropy (La0.2Nd0.2Sm0.2Eu0.2Gd0.2)Ce2O7 in different aggressive molten salt

High-entropy (La0.2Nd0.2Sm0.2Eu0.2Gd0.2)Ce2O7 (HECO) was synthesized as a potential thermal barrier material. The hot corrosion behavior of HECO in the mixture of V2O5 + Na2SO4 with variable aggressiveness was investigated from reaction crystallization kinetics, as well as La2Ce2O7 (LCO). Overall, HECO exhibits smaller corrosion depth than LCO except for partial exfoliation. Sluggish diffusion effect of HECO greatly inhibits nucleation of corrosion products, while a horizontal growth is triggered along (001) crystal plane, leading to a reduction in corrosion depth. Meanwhile, with the aggressiveness of molten slat strengthened, reaction kinetics is accelerated and arouses a sharp alleviation of corrosion.

Automated summary

The high-entropy material HECO shows smaller corrosion depth than LCO except for partial exfoliation. The sluggish diffusion effect of HECO inhibits nucleation of corrosion products and leads to a reduction in corrosion depth through horizontal growth. Additionally, the correlation between the aggressiveness of molten salt and the corrosion alleviation is observed.