HF-free molten salt route for synthesis of highly efficient and water-resistant K2SiF6:Mn4+ for warm white LED
HF-free molten salt route for synthesis of highly efficient and water-resistant K2SiF6:Mn4+ for warm white LED
复制标题
用于合成用于暖白光 LED 的高效防水 K2SiF6:Mn4 的无 HF 熔盐路线
DOI：
10.1111/jace.17410
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Libin Xia
中科院分区：
文献类型：
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作者：
Qiyun Wu;Chenxing Liao;Jinquan Pan;Xinyu Ye;Weixiong You;Libin Xia
用绿色环保的方法制备高效、防水的温白光发光二极管(WLED)用掺Mn4+红色荧光粉已成为研究的热点之一。在此，我们设计了一种新的绿色熔盐路线来合成K2SiF6：Mn4+红色粉末，用熔融的NH4Hf2盐代替HF溶液作为反应介质。结果表明，KMnO4和MnF2在NH4Hf2熔盐中通过还原反应生成Mn4+，得到的掺杂Mn4+的K2SiF6在蓝光激发下表现出632 nm的红光发射。所得产物在水中浸泡24小时后，发光强度几乎保持浸泡前的100%，发射峰形保持不变。通过加热和降温过程中发光光谱强度的温度变化来评价样品的热稳定性。以蓝筹、K2SiF6：Mn4+和商品黄色荧光粉(Y3Al5O12：Ce3+)为原料，制备了显色指数Ra=87.1、相关色温Cct=0.3536K、发光效率高(116.99×lm·W−1)的温白光发光二极管。
It has been one of the hot issues to prepare the red‐emitting Mn4+‐doped fluoride phosphors with highly efficient and waterproofness for warm white‐light‐emitting diodes (WLEDs) by the green and environmentally friendly method. Herein, we design a novel green molten salt route to synthesize K2SiF6:Mn4+red powder using molten NH4HF2salt instead of HF liquor as the reaction medium. The results show that KMnO4and MnF2could produce Mn4+in NH4HF2molten salt through a reduction reaction, and the resulting Mn4+‐doped K2SiF6exhibited a bright red emission peaked at 632 nm under blue light excitation. The luminescence intensity of the as‐obtained product after immersing into water for 24 hours maintain nearly 100% of that before soaking and emission peak shape remains unchanged. The thermal stability of the sample was evaluated by temperature‐dependent luminescence spectral intensity during heating and cooling. Furthermore, a warm white‐light‐emitting diodes (WLEDs) with an excellent color rendering index (Ra = 87.1), lower correlated color temperature (CCT = 3536K), and high luminous efficacy (116.99 lm·W−1) was fabricated based on blue chip and K2SiF6:Mn4+and commercial yellow phosphor (Y3Al5O12:Ce3+).