核壳发光材料中ZrO2/BN阻挡层的形成及其作用机理研究

Core-shell structure materials have drawn great interest due to its promising properties. Research of core-shell structured phosphors is focused on preparation and structure tuning. However, decreasing in luminescent intensity of this kind of materials caused by interface diffusion is neglected. Based on the exceptional chemical and thermal stability of ceramics, this project propose a layer of ZrO2 and BN films are inserted between the core and shell of the core-shell structured phosphors, as interlayer, to block interface diffusion which is always growing in intensity at high temperatures. ZrO2 and BN films are going to prepare by the Sol-gel method, Solvent thermal and H3BO3 nitrification. XPS and EPMA are used to analysis distribution of elements in interlayers in order to obtain diffusion information of the related elements. Measuring PL properties of the prepared samples would be a help for revealing relation between composition and structure of interlayer and PL properties of the product. Understanding mechanism of the interlayers on decreasing diffussion speed the improving PL intensity in core-shell structured phosphors. The produced core-shell structured phosphors with ZrO2 and BN interlayer are expected with high PL intensity and stable core-shell structure. The aim of the project is to explore the effect of ZrO2 and BN films on the luminescent properties of core-shell structured phosphors and to discuss the possibility mechanism to block interface diffusion.

核壳结构发光材料的研究主要集中于制备和结构调控方面，而较少关注由于核壳间界面扩散所引起的发光强度下降。本项目基于陶瓷材料的稳定性，提出以ZrO2和BN薄膜作为核壳结构发光材料界面扩散阻挡层的研究思路。拟采用层层自组装法、溶剂热或氮热还原等方法在核表面制备不同致密度的ZrO2和BN薄膜，再进一步包覆发光材料壳层，制备具有界面扩散阻挡层的核壳结构发光材料；通过表征核/壳材料组成元素在阻挡层中的分布，阐明核/壳材料元素随阻挡层和热处理条件变化的扩散规律；研究具有扩散阻挡层的核壳结构发光材料的性质，揭示阻挡层的组成和结构与材料性能的关系；阐明扩散阻挡层对于降低界面扩散速率的作用机理；期待制备的具有界面扩散阻挡层的核壳结构发光材料能在节约稀土原料、保持核壳结构的同时具有较高的发光强度，解决现有核壳结构发光材料存在的过低的合成温度所致的发光强度低等出问题，实现核壳结构发光材料设计和制备技术的进步。

核壳结构发光材料的研究主要集中于制备和结构调控方面，而较少关注由于核壳间界面扩散所引起的发光强度下降。本项目基于陶瓷材料的稳定性，提出了以ZrO2和BN作为核壳结构发光材料界面扩散阻挡层的研究思路，以C球、SiO2球、TiO2球为内核，采用层层自组装法、溶剂热等方法在不同组成内核表面制备了不同厚度和致密度的ZrO2和BN作为扩散阻挡层，进一步通过沉淀法、水热法和层层组装法在阻挡层外包覆了Y2O3:Eu等发光材料层，获得了具有界面扩散阻挡层的核壳发光材料和以陶瓷层为支撑的空心发光材料。系统研究了制备条件、阻挡层组成、厚度和密度变化对核壳结构发光材料及空心发光材料性能的影响，发现在以SiO2球、TiO2球为内核所制备的核壳结构发光材料中，ZrO2和BN界面层可阻止SiO2或TiO2与Y2O3:Eu间的反应，因而显著提高了核壳结构发光材料的发光强度。. 制备了以BN为界面层的C@BN@Y2O3：Eu材料，在除去C球后BN层可以稳定Y2O3:Eu，而且BN的存在可提供一定量的B和N掺杂，有助于提高空心材料的发光强度。.以Au@C微球为模板，合成了多层结构Au@C@Y(OH)CO3和Au@C@YVO4:Eu，以及C@BN@Y(OH)CO3, 高温煅烧获得了中空的Au@Y2O3:Eu3+、Au@ YVO4:Eu和BN@Y2O3:EuO微球， Au@Y2O3:Eu3+、Au@ YVO4:Eu和BN@Y2O3:EuO空心微球有良好的发光性能。Au@Y2O3:Eu3+空心微球在具备较好的发光性能的同时，也具有较为突出的光催化性能。. 该项工作的完成对于节约稀土原料，解决现有核壳结构发光材料存在的过低的合成温度所致的发光强度低等问题，实现核壳结构发光材料设计和制备技术的进步有积极的推动作用。