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Gd_2O_2S:Eu~(3+) nanoparticles were synthesized using two step process consisting of sulfuration of basic carbonates obtained by homogenous precipitation.Annealing of lanthanide nitrates at total concentration of 5×10~(-3) mol/L in a water solution containing relatively high,three molar concentration of urea ensured the optimal conditions for the reproducible preparation of uniform and small spherical particles.During sulfuration step elemental sulfur was mixed with precursor which eliminated necessity of using an auxiliary furnace and provided sulfur-reach reaction atmosphere.Such optimized protocol afforded synthesis of spherical and non-agglomerated nanoparticles with diameter smaller than 100 nm.The precursors morphology was maintained,but particles size was reduced by 15%-20%during sulfuration.The results indicated that higher emission intensity was observed for Gd_2O_2S:Eu~(3+)(8%)oxysulfide sample synthesized using crystalline Gd(CO_3)OH precursor,than for that obtained from amorphous Gd_2(OH)_2(CO_3)_2·H_2O precursor,although some further efforts to improve morphology of the former are still required.
Gd_2O_2S: Eu ~ (3+) nanoparticles were synthesized using two step process consisting of sulfuration of basic carbonates obtained by homogenous precipitation. Annealing of lanthanide nitrates at total concentration of 5 × 10 ~ (-3) mol / L in a water solution containing relatively high, three molar concentration of urea guaranteed the optimal conditions for the reproducible preparation of uniform and small spherical particles. During quenching step elemental sulfur was mixed with precursor which eliminated necessity of using an auxiliary furnace and providing sulfur-reach reaction atmosphere. protocol afforded synthesis of spherical and non-agglomerated nanoparticles with diameter smaller than 100 nm. The precursors morphology was maintained, but the particle size was reduced by 15% -20% during sulfuration. The results indicated that higher emission intensity was observed for Gd 2 O 2 S: Eu ~ (3 +) (8%) oxysulfide sample synthesized using crystalline Gd (CO_3) OH precursor, than for that obtained from am orphous Gd_2 (OH) _2 (CO_3) _2 · H_2O precursor, although some further efforts to improve morphology of the former are still required.