Doped Two Dimensional Metal Chalcogenides as Printable White Light Phosphors

特别是2D金属二硫属化物（TMDC）的掺杂提供了一种简便的途径，通过该途径可以生产具有先进光电性能的新型先进复合纳米材料。[1]用镧系元素离子掺杂二维TMDC提供了一个有吸引力的机会，通过该机会来扩展后者的先进材料性能。镧系元素（III）离子（Ln 3+）由于其独特的光物理性质而长期被研究，所述光物理性质包括长寿命（以ms计）、强烈的线状发射轮廓，以及由于在每个离子中缺乏晶体场偏好而通过明智地选择镧系元素离子（例如用于红色光子发射的Eu 3+、用于绿色发射的Tb 3+、Yb 3+用于近红外发射，Gd 3+用于强顺磁性。[2]We最近表明，2D二硫化钼纳米片可以同时用Eu 3+和Gd 3+络合物官能化。所得纳米材料显示出来自电磁光谱的红色区域（570 - 720 nm）中的Eu 3+发射的0.8 ms的长光致发光发射寿命，其源自5D 0-> 7 Fj电子f-f跃迁，同时在EPR光谱中具有强顺磁响应，因此可以用作双峰光学探针/磁共振成像造影剂。[3]We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2D材料的特性。掺杂混合的发光镧系元素络合物（例如Sm 3+、Dy 3+、Eu 3+和Tb 3+）可以产生具有白色光发射的固态磷光体。这些新材料的印刷可能导致用于柔性照明的柔性白色光磷光体。该项目将涉及Ln掺杂的2D材料的合成和表征，通过各种技术研究其物理学，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将使载流子动力学能够确定到亚皮秒时间尺度，并将使我们深入了解辐射和非辐射途径[4]。将开发可印刷油墨并阐明其性质。参考文献[1] Tedstone等人Chem Mater 2016，28，1965。[2]刘易斯等Coord. Rev.2014，273，213。[3]McAdams等人，Adv Func. Mater. 2017，1703646 [4] Kime等人J. Phys. Chem. C 2017，121，22415。

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.