微波水热合成NaLa(MoO_4)_2:Eu^(3+)微晶及其发光性能

Microwave-hydrothermal synthesis of NaLa( MoO_4)_2:Eu^(3+) microcrystals and luminescent properties

采用微波水热法合成形貌规整、尺寸均一的短棒状和树枝状NaLa(MoO4)2:Eu3+微晶。研究反应温度、反应物浓度和反应时间对产物形貌的影响。结果表明:在反应物浓度为10 mmol/L条件下,当反应温度为100℃时,产物为纳米片状结构;反应温度为150℃时,得到长约5μm、直径约500 nm的棒状结构产物;当反应物浓度为40mmol/L,反应温度为150℃时,产物为树枝状结构。荧光性能分析表明,棒状和树枝状微晶在464 nm蓝光有效激发下,均发射出614 nm红光,对应于Eu3+的5D0→7F2跃迁。棒状晶体的发光强度约为树枝状的10倍,这是由于棒状晶体较强的激发强度引起的。

Uniform NaLa（MoO4） 2 microcrystals,including rod-like and dendrite-like,were synthesized by a microwave-hydrothermal method.The effects of reaction parameters,such as reaction temperature,concentration,and reaction time on the morphology and size of NaLa （MoO4）2 microcrystals were investigated.Results showed that with reagent concentration of 10 mmol/L,nano-plates were obtained at 100 ℃,and 1D rod-like microcrystals with about 5 μm in length and 0.5 μm in width were obtained at 150 ℃.With concentration of 40 mmol/L,dendritic microcrystals were obtained.Photoluminescence spectra （PL） revealed that the rod-like and dendrite-like microcrystals showed strong red light at 614 nm associated with 5D0→7F2 transition of Eu3＋ at 464 nm blue excitation.The PL intensity of rod-like microcrystals was as 10 times as that of dendrite-like microcrystals,thus it was attributed to the strong excitation in the ultraviolet region.