Hydroflux Synthesis and Structural Phase Transition of Rare-Earth Borate Hydroxides Na₂[RE(BO₃)(OH)₂] (RE=Y, Gd-Er).

ABSTRACT: Reacting RE₂O₃ and H₃BO₃ in an ultra-alkaline NaOH hydroflux at about 250 °C yielded pure, crystalline samples of Na₂[RE(BO₃)(OH)₂] (RE=Y, Gd-Er). The compounds dehydrate to Na₃RE(BO₃)₂ upon heating in air to about 500 °C. Na₂[RE(BO₃)(OH)₂] (RE=Tb-Er) are photoluminescent under UV radiation. Their UV-Vis spectra show the typical absorptions associated with 4f-4f transitions and absorption edges in the UV (band gaps ≥5.7 eV). The RE³⁺ cation is coordinated by seven oxygen atoms, which define a distorted pentagonal bipyramid. The bipyramids share trans-edges of their base forming infinite chains. Triangular (BO₃)^3- gro

SUBMITTER: Li Y 

PROVIDER: S-EPMC11618041 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature