Topotactic Conversion into Gd2O3:Bi3+, Eu3+ Nanosheets from Flaky LGdH Precursor and Photoluminescence Properties

The Bi3+ sensitized Gd2O3: Eu3+ nanosheets were prepared from the sodium benzoate intercalated layered rare-earth hydroxide (LRH), by calcination at 800 degrees. The precursor Gd(1.9-X)Eu0.1BiX(OH)(5)NO3 center dot 1.5H(2)O was synthesized by solvothermal reaction. XRD and TEM suggested that the precursor LRH were crystallites and crystallographic orientation. After 800-degree calcination, the mono-crystalline nature and sheet-like morphology reserved. The Gd2O3: Bi3+, Eu3+ therefore exhibited characteristic red emission of Eu3+ at 611 nm under the photo-excited 335 nm, following the energy transfer from 6s(2) -> 6s6p of Bi3+ to Eu3+. The PL quantum yield of Gd2O3: Bi3+ was 24% at a Bi3+ concentration of 4 at%.