An obvious rolling process in the synthesis of Y2O3:Eu3+ micro-urchins built from nanoscrolls

Abstract

We report a novel method to synthesize Y₂O₃:Eu³⁺ nanoscrolls by hydrothermal and post-heat treatments. In the hydrothermal process, a precursor compound with well-defined urchinlike morphology has been obtained with the aid of BO₃³⁻ and L-glutamic acid. The formed micro-urchins consist of numerous nanoscrolls rolled up from nanosheets. Condition experiments and analysis reveal that BO₃³⁻ anions and L-glutamic acid were vital for the rolling process of the nanoscrolls. Under ultrasound treatment, the micro-urchins can break into separated nanoscrolls. In a subsequent calcination process, the as-prepared precursors can transform into Y₂O₃:Eu³⁺ with the same morphology. The resultant Y₂O₃:Eu³⁺ micro-urchins exhibit a strong red emission corresponding to the ⁵D₀ →⁷F₂ transition of the Eu³⁺ ions under UV light excitation. Moreover, our method may provide a new way to realize the “rolling-up” process of other compounds.