Study on water vapor corrosion resistance of rare earth monosilicates RE2SiO5 (RE = Lu, Yb, Tm, Er, Ho, Dy, Y, and Sc) from first-principles calculations

• Main Authors: Jing Han, Yanfei Wang, Rongjun Liu, Di Jiang
• Format: Article
• Language: English
• Published: Elsevier 2018-10-01
• Series: Heliyon
• Subjects: Materials chemistry; Inorganic chemistry; Structural engineering
• Online Access: http://www.sciencedirect.com/science/article/pii/S2405844018339495
• ISSN: 2405-8440

Corrosion resistance of rare earth monosilicates (RE2SiO5, RE = Lu, Yb, Tm, Er, Ho, Dy, Y, and Sc) in water vapor has been studied using the first-principles calculations. The results show that the water vapor corrosion resistance of RE2SiO5 demonstrates the following order: Sc2SiO5 > Dy2SiO5 > Y2SiO5 > Ho2SiO5 > Er2SiO5 > Yb2SiO5 > Tm2SiO5 > Lu2SiO5. To further improve their water vapor resistance, a doping strategy has been employed for the first time. Two scenarios have been investigated: one is a half mole proportion of substitution of various rare earth elements for Yb in the Yb2SiO5 lattice; the other is a half mole fraction substitution of rare earth elements in RE2SiO5 (RE = Lu, Yb, Er and Y) by scandium. It is unveiled that the water vapor resistance of YbScSiO5 and YScSiO5 has been greatly improved in contrast to other rare earth monosilicates. The current study provides guidelines for the selection of environmental barrier coatings with a better water vapor corrosion resistance.