Doped Two Dimensional Metal Chalcogenides as Printable White Light Phosphors

特别是二维金属二硫族化合物（TMDCs）的掺杂，为生产具有先进光电性能的新型先进复合纳米材料提供了一条简便的途径。掺杂镧系离子的二维TMDCs为扩展后者的先进材料性能提供了一个有吸引力的机会。镧系（III）离子（Ln3+）因其独特的光物理性质而长期受到研究，包括长寿命（以毫秒为单位），强烈的线状发射曲线，以及由于每个离子缺乏晶体场偏好，通过明智地选择镧系离子（例如Eu3+用于红色光子发射，Tb3+用于绿色发射，Yb3+用于近红外发射，Gd3+用于强顺磁性）来调节光致发光或磁性的能力。我们最近发现二维二硫化钼纳米片可以同时被Eu3+和Gd3+配合物功能化。所得纳米材料在5D0 -> - 7Fj电子f-f跃迁产生的电磁波谱（570 - 720 nm）红色区域的Eu3+发射中显示出0.8 ms的长光致发光寿命，同时在EPR光谱中具有较强的顺磁响应，因此可以用作双峰光学探针/磁共振成像造影剂。我们现在希望通过探索可用于掺杂的镧系元素的整个范围来扩展我们可以赋予二维材料的性质。掺杂混合发光镧系配合物（如Sm3+， Dy3+， Eu3+和Tb3+）可以得到具有白光发射的固态荧光粉。这些新材料的印刷可以产生柔性白光荧光粉，用于柔性照明。该项目将涉及镧掺杂二维材料的合成和表征，通过各种技术研究其光物理特性，包括温度依赖性光致发光和吸收光谱，共聚焦显微镜和量子产率测量。瞬态光致发光和超快瞬态吸收光谱学将使载流子动力学能够确定到亚皮秒的时间尺度，并将使我们深入了解辐射和非辐射途径。将开发可印刷油墨并阐明其特性。参考文献[b] Tedstone et al .化学学报，2016,28,1965。[b]刘易斯等人。Rev. 2014, 273, 213。[3]麦克亚当斯等人，广告Func。[j] .物理学报，2017,17(6):481 - 481。化学。中文信息学报，2017,21,22415。

Doping of 2D metal dichalcogenides (TMDCs) in particular, provides a facile route by which to produce new advanced composite nanomaterials that have advanced optoelectronic properties. [1] Doping of two-dimensional TMDCs with lanthanide ions provides an attractive opportunity by which to extend the latter's advanced materials properties. Lanthanide(III) ions (Ln3+) have long been investigated for their unique photophysical properties, which include long lifetimes (in ms), intense line-like emission profiles and, due to the lack of crystal field preference in each ion, the ability to tune photoluminescence or magnetic properties by judicious choice of lanthanide ion e.g. Eu3+ for red photonic emission, Tb3+ for green emission, Yb3+ for emission in the near infrared and Gd3+ for intense paramagnetism.[2]We have recently shown that 2D molybdenum disulfide nanosheets can be functionalised with both Eu3+ and Gd3+ complexes simultaneously. The resulting nanomaterials display long photoluminescence emission lifetimes of 0.8 ms from the Eu3+ emission in the red region of the electromagnetic spectrum (570 - 720 nm), derived from the 5D0 -> 7Fj electronic f-f transitions, whilst having strong paramagnetic response in EPR spectra, and thus could be used as a bimodal optical probe / magnetic resonance imaging contrast agent. [3]We now wish to extend the properties that we can impart to 2D materials by exploring the whole range of lanthanide elements available for doping. Doping with mixed optical emitting lanthanide complexes (e.g. Sm3+, Dy3+, Eu3+ and Tb3+) could lead to solid state phosphors which have white light emission. Printing of these new materials could lead to flexible white light phosphors for flexible lighting. The project will involve the synthesis and characterisation of Ln-doped 2D materials, the study of their photophysics by various techniques including temperature-dependent photoluminescence and absorption spectroscopy, confocal microscopy and quantum yield measurements. Transient photoluminescence and ultrafast transient absorption spectroscopy will enable carrier dynamics to be determined down to a sub-picosecond time-scale and will give us insight into the radiative and non-radiative pathways [4]. Printable inks will be developed and their properties elucidated.References[1] Tedstone et al Chem Mater 2016, 28, 1965. [2] Lewis et al Coord. Chem. Rev. 2014, 273, 213. [3] McAdams et al, Adv Func. Mater. 2017, 1703646 [4] Kime et al J. Phys. Chem. C 2017, 121, 22415.