可视化磁光复合材料温度传感器的构建及界面调控研究

Fabrication of the magnetic and luminescent composite nanomaterials with high performance is the key for their biomedical and magneto-optoelectronic applications. In this project, the wide bandgap semiconductor interface as barrier layer is uased to change the electronic coupling between magnetic nanoparticles and the luminescent layers as well as two luminescent layers, control charge transport processes, and obtain high-performance magnetic and dual-wavelength luminescent nanocomposites with highly efficient photoluminescence and strong magnetic properties. The research works includes the following respects: 1) through flexible chemical methods, the preparation of FePt magnetic nanoparticles coated with ZnS shell, and study the effect of the shells on the morphology and magnetic properties of FePt nanoparticles. 2) two quantum wells with luminescent layer/interface layer/luminescent layer are grown above the strongly magnetic nanoparticles, the nanostructure with dual-wavelength fluorescence emission can be achieved through regulation of the height and thickness of the interface barrier layer and electronic coupling degree. This project will focus on the effects of the interface barrier layer and the energy level structure of composite structure on the magnetic and luminescent properties. 3) the charge transport processes between the magnetic nanoparticles and luminescent layers as well as two luminescent layers (quantum wells) will be understood, and the fabricating methods and conditions of the magnetic and luminescent core/shell nanostructures will be optimized for achievement of high performance nanocomposites. Based on the fluorescence thermosensitive difference of the intrinsic and doped semiconductor layers, the ultra-sensitive, high-precision and visual temperature sensor can be realized by the signal output of the fluorescence ratio and the color changes of the composite nanomaterials. Therefore, the study on these questions above is very important for us to further optimize the magnetic and luminescent properities of these nanostructures and improve their performances for applications of magnetic resonance and optical imaging.

构建高性能磁性/荧光复合纳米材料是其应用于生物医药和光电子领域的关键问题。本项目利用宽带隙半导体作为界面势垒层，改变半导体发光层与磁性粒子以及两个发光层之间的电子耦合，控制电荷传输过程，获得高效的双波长发光和强磁性的复合纳米材料。通过柔性的化学方法，首先在FePt磁性粒子表面包覆ZnS壳层，研究粒子结构和磁性变化。再在强磁性粒子表面包覆发光层/界面层/发光层双量子阱结构壳层，调控界面势垒层的高度和厚度，改变两个发光层之间的电子耦合程度，实现双波长荧光发射。着重研究界面势垒层及其能级结构对复合结构磁性和发光性质的影响，优化合成方法和条件，构建最佳的复合纳米结构。利用本征半导体发光层和掺杂发光层的荧光热敏性差异，通过比率荧光信号输出和颜色的改变，实现超灵敏、高精度和可视化温度传感。上述关键科学问题的研究，对发展高性能磁性荧光复合纳米结构和开展它们的磁共振及光学成像研究具有重要科学意义。

我们按照本项目的研究目标和方案，开展了磁光复合纳米材料的制备及发光性能研究。通过控制化学反应条件，制备了一系列的PtFe纳米粒子，系统研究了不同反应条件对粒子形貌的影响，并探索了ZnS等宽带隙材料在其表面如何实现有效包覆，优化了PtFe@ZnS的制备条件，优化了PtFe@ZnS@CdSe、PtFe@ZnS@CuInS、CdSe@ZnS@CdSe复合材料的制备方法，并深入研究了其光学性质，充分分析了ZnS能垒的宽度和厚度对最外层发光性能的影响，充分理解了界面量子阱对电荷传输的影响机制。我们也将能带工程理论用于光学性质的调控拓展到钙钛矿发光材料研究领域，制备了一系列Sb3+:Cs2NaInCl6、Mn:Cs2Na1-xAgxBiCl6、Te4+：Cs2SnCl6、Mn:CsPbCl3、Mn:Cs3Pb6.48Cl16、无机-有机杂化材料C10H12N2MnBr4和C5H6NMnBr3单晶、Te：CdS纳米线等系列发光材料，并深入理解和研究了其发光物理过程和光学性质。我们也拓展了复合材料在生物传感方面的研究，研制了一种检测乙型肝炎抗原的新型无标记安培免疫传感器，提出了一种利用一次性电化学传感器检测血红蛋白的电化学方法。我们发表了SCI论文10篇，中科院一区文章4篇，二区文章5篇，三区文章1篇，其中申请人为通讯作者的有8篇，申请国家发明专利3件，出版专著1部；培养硕士研究生2名，在读博士研究生4名，在读硕士研究生7名，完成了本课题所设定的目标。