Ultrasonic irradiation-promoted one-pot synthesis of CH3NH3PbBr3 quantum dots without using flammable CH3NH2 precursor
Ultrasonic irradiation-promoted one-pot synthesis of CH3NH3PbBr3 quantum dots without using flammable CH3NH2 precursor
复制标题
超声辐照促进不使用易燃CH3NH2前驱体一锅法合成CH3NH3PbBr3量子点
DOI：
10.1088/2053-1591/aa5c01
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Yiping Cui
中科院分区：
文献类型：
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作者：
Han Jiang;Chunlei Wang;Changgui Lv;Shuhong Xu;Li Zhu;Ruohu Zhang;Yiping Cui
目前，文献报道的CH3NH3PbBr3量子点的合成通常包括两步：首先由易燃的CH3NH2与HBr反应生成CH3NH3Br，然后再生成CH3NH3PbBr3量子点。为了避免使用危险的CH3NH2，本工作开发了一种新的一锅法合成CH3NH3PbBr3量子点，使用安全和商业可用的反应物（CH3NH3Cl，KBr和PbCl2）。结果表明，超声波处理在CH3NH3PbBr3量子点的合成过程中起着关键作用.没有超声辐射，在加热或剧烈搅拌下不可能合成CH3NH3PbBr3量子点。在不同的超声辐照时间间隔取的样品的等分试样显示出随时间变化的发射波长的红移。这表明首先形成CH3NH3PbCl3量子点，然后通过超声促进的卤化物交换形成CH3NH3PbBr3量子点。此外，通过控制超声辐照时间，还可以制备出发射波长可调的混合CH3NH3PbClxBr3 − x量子点。与以前的两步法相比，目前的一锅法更简单，耗时更少，并且不使用易燃的CH3 NH2。所制备的CH3NH3PbBr3量子点的光致发光（PL）量子产率（QY）与文献报道的量子产率相当。更重要的是，CH 3 NH 3 PbCl x Br 3 − x量子点的超声波时间控制发射波长也提供了一种调整量子点发射的替代方法，以控制卤化物比例的传统方法。
At present, the CH 3 NH 3 PbBr 3 quantum dots (QDs) reported in the literature usually contain two synthesis steps: the initial preparation of CH 3 NH 3 Br via the reaction of flammable CH 3 NH 2 and HBr, together with the subsequent formation of CH 3 NH 3 PbBr 3 QDs. To avoid the use of dangerous CH 3 NH 2, this work develops a novel one-pot method for synthesizing CH 3 NH 3 PbBr 3 QDs using safe and commercially available reactants (CH 3 NH 3 Cl, KBr and PbCl 2). It is found that ultrasonic treatment plays a key role during the synthesis of CH 3 NH 3 PbBr 3 QDs. Without ultrasonic irradiation, it is not possible to synthesize CH 3 NH 3 PbBr 3 QDs under heating or vigorous stirring. Aliquots of samples taken at different ultrasonic irradiation time intervals show a time-dependent redshift in the emission wavelength. This suggests the formation of CH 3 NH 3 PbCl 3 QDs first, followed by the formation of CH 3 NH 3 PbBr 3 QDs through ultrasonically promoted halide exchange. Moreover, mixed CH 3 NH 3 PbCl x Br 3− x QDs with a tunable emission wavelength can also be prepared through this one-pot method by controlling the ultrasonic irradiation time. In comparison to the previous two-step method, the current one-pot method is simpler, less time-consuming and does not use flammable CH 3 NH 2. The as-prepared CH 3 NH 3 PbBr 3 QDs show a comparable photoluminescence (PL) quantum yield (QY) to that of the literature. What is more, the ultrasonic time-controlled emission wavelength of CH 3 NH 3 PbCl x Br 3− x QDs also provides an alternative way of tuning QD emission to the traditional way of controlling the halide ratios.