Objective:To elucidate the effects of different morphologies and sizes of micro/nanomaterial on luminescence properties.Methods:Lu2O3:Eu3+micro-/nanocrystals with different morphologies were synthesized hydrothermally,and the effects of precursor concentration,reaction time,pH,and alkali source on morphology and photoluminescence were investigated.Products were calcined and then characterized for morphology and photoluminescence.Spectra were collected with 250 nm excitation,focusing on the O2-→Eu3+charge-transfer band(CTB)and Eu3+f-f transitions.Results:The use of NaOH,aqueous ammonia,or triethylamine yielded monodisperse square nanosheets after calcination,while the use of urea produced monodisperse and uniform nanospheres.Fluorescence measurements showed a strong CTB near 250 nm.Under 250 nm excitation,the emission comprised multiple peaks,with the the strongest being the 5D?→7F2 hypersensitive transition at 614 nm.Conclusions:In the hydrothermal system,alkali source and reaction parameters provide significant control over the morphology and size of Lu2O3:Eu3+micro-/nanocrystals.The morphology-dependent emission is dominated by red light at 614 nm(5D?→7F).

Objective:To elucidate the effects of different morphologies and sizes of micro/nanomaterial on luminescence properties.Methods:Lu2O3:Eu3+micro-/nanocrystals with different morphologies were synthesized hydrothermally,and the effects of precursor concentration,reaction time,pH,and alkali source on morphology and photoluminescence were investigated.Products were calcined and then characterized for morphology and photoluminescence.Spectra were collected with 250 nm excitation,focusing on the O2-→Eu3+charge-transfer band(CTB)and Eu3+f-f transitions.Results:The use of NaOH,aqueous ammonia,or triethylamine yielded monodisperse square nanosheets after calcination,while the use of urea produced monodisperse and uniform nanospheres.Fluorescence measurements showed a strong CTB near 250 nm.Under 250 nm excitation,the emission comprised multiple peaks,with the the strongest being the 5D?→7F2 hypersensitive transition at 614 nm.Conclusions:In the hydrothermal system,alkali source and reaction parameters provide significant control over the morphology and size of Lu2O3:Eu3+micro-/nanocrystals.The morphology-dependent emission is dominated by red light at 614 nm(5D?→7F).