有机敏化层状稀土氢氧化物(LRH)发光复合体的构筑与性能研究

Consindering the drawback of that phosphors sensitized by inorganic matrixs are liable to absorb water and complexes with organic sensitisers have bad chemical, thermal and photolytic stability, this project intend to investigate the fabrication of layered rare-earth hydroxides (LRH) composites sensitized by organic compounds and study their structures and luminescent properties. Single LRHs with only one rare-earth element in the host layer such as LEuH and LTbH and Gd3+, Y3+ doped LRHs are synthesised. Nanosheets derived from delamination are intended to construct function films using layer-by-layer (LBL) and liquid-liquid interface assembly methods. Oxides, that is, inorganic sensitized luminescent materials can be obtained after calcination. Introducing organic sensitizer into host layer, we can fabricate thin film materials through delamination/reassembly method, build block materials by ion-exchange and swelling/restoration or 'one-pot' method that created by our group, which create a new way for preparing organic/inorganic composites. At the same time, the host layer element and organic species between layers can be tuned to yield multicolor materials. Additionally, calcining the organic sensitized luminescent materials to make the organic compounds lose partially and oxides generate simultaneously. Research the luminescent property when inorganic and organic sensitizer coexist and explore the relationship between structure and luminescence property. LRH is a newly developed research area in the world. The thin-film materials assembled form inorganic nanosheets and organic guests can enhance the stability of organic materials and improve the luminescent properties. This study is an unique idea with strong innovation and belongs to cross-integration of inorganic layer materials chemistry, organic chemistry, rare-earth chemistry, showing important theoretical significance and application value.

针对无机敏化发光材料存在易吸水使发光减弱及配合物光、热、化学稳定性差等缺陷，本项目提出构筑有机敏化层状稀土氢氧化物(LRH)发光复合体，增强有机物稳定性同时改善发光性能。合成Eu3+、Tb3+、Gd3+、Y3+等单一或掺杂层板的LRH,剥离为纳米片以LBL法或相界面法组装薄膜，焙烧得无机敏化材料；引入有机敏化客体，利用离子交换法或我们开发的膨润/回复、"一锅法"等制备粉状材料，剥离/再配列法等组装薄膜，开创有机/无机复合体制备新途径。改变层板元素或层间有机物种类构筑多色发光材料。将有机敏化材料焙烧使有机物部分失去同时生成氧化物，研究有机、无机敏化剂共存时的发光性能，探讨结构与性能的关系。LRH是国际新近发展的领域，纳米片再配列组装复合体是国际领先的方法。本课题研究思路独具特色，具有较强创新性，是无机层材料化学、有机化学、稀土化学等交叉融合基础上的课题，具有重要理论意义和应用

有机-无机杂化发光材料，由于其独特结构和发光性能，日益受到研究者关注。基于无机有机组分间的相互作用，可形成性能多样的复合体。层状稀土氢氧化物(LRHs)是一类新兴的二维主体材料，其层板带正电可结合阴离子以构建优良发光材料。通过改良的均匀沉淀法合成出含Eu3+、Tb3+、Gd3+、Y3+等单一元素层板或掺杂层板LRHs, 如NO3-LEuH、Cl-LEuH、NO3-LYH:Eu、Cl-LYH:Eu、NO3-LGdH:Eu、NO3-LTbH、NO3-LGdH、NO3-LYH、NO3-LYH:Tb等，在层间插入苯多羧酸和氨基酸类有机物，研究对层板Eu3+、Tb3+发光性质的影响，发现苯多羧酸类化合物由于存在有机物到Eu3+、Tb3+的能量转移，从而敏化其发光；而氨基酸类化合物由于存在-NH2、-OH等高能振动基团，通过非辐射弛豫的形式使激发态的Eu3+、Tb3+失活，淬灭层板稀土离子的发光，可作为荧光探针探测生物体系氨基酸的存在；将芳香羧酸类有机敏化剂-LYH:Eu复合体进行高温焙烧，研究煅烧产物的结构转型和发光性质，获得其变化规律；将有机荧光分子如8-羟基-1,3,6-三磺酸基芘(HPTS)和具发色团的香豆酸类有机物及表面活性剂1-辛烷磺酸钠(OS)共插层到LEuH、LTbH层间，由于有机客体与层板稀土离子的协同作用，改善了有机物的发光（如得到纯化的蓝光发射），构建出新颖的杂化发光材料；另外发现OS的存在不但能起到稀释有机物发色团以避免因分子聚集发生的荧光淬灭，使复合体的发光性能得以保持或改善，而且可使有机LRH复合体在甲酰胺中容易实现剥离，开拓了LRHs复合体剥离的新途径，为组装薄膜发光材料提供了便利。探讨了以上复合体的结构与发光性能的关系，获得许多创新性研究成果。该项目丰富了插层化学、复合材料化学、稀土发光化学等的知识积累，具有重要学术价值和应用前景。