硅量子点以其特殊的光物理性能和良好的生物相容性、无毒性，有望成为新兴的生物荧光标记材料。为了实现硅量子点在生物医学动态研究中的应用，光稳定性已成为评价新型硅量子点的关键参数。然而光稳定性的受控因素仍然是未解之谜，对于该科学问题的研究则首先需要准确地表征硅量子点的微观结构。基于上述科研需求，本项目拟选取具有优异光稳定性的生物荧光硅量子点(SiNPs)为研究对象，主要使用高分辨固体核磁共振（SSNMR）技术研究SiNPs的微观结构，并归纳总结出适用于硅量子点结构研究的SSNMR方法。此外，通过讨论荧光淬灭过程中SiNPs的结构变化，将有目的性地调控SiNPs的配体、界面硅层或硅纳米晶核的结构，同时结合光稳定性的表征，探索影响硅量子点光稳定性的结构因素，提出具有理想光稳定性的硅量子点的结构模型，为合成研究者研发新型硅量子点提供结构设计策略和理论依据。

Silicon quantum dots(SiQDs) have emerged as a new class of luminescent materials owning to their fascinating optical properties, favorable biocompatibility and non-toxicity. For biological and biomedical application, especially for long-term and real time imaging, photo stability has become a crucial optical property for evaluating novel SiQDs. However, the method to improve SiQDs photo stability is still under investigation, which relates to the structures in molecular scale. In this work, a functional silicon quantum dots with high photo stability (SiNPs) will be studied by using advanced solid state nuclear magnetic resonance(SSNMR) techniques together with high resolution TEM (HRTEM), according to which a method for characterizing SiQDs structures will be proposed. In addition, the impact of UV irradiation on SiNPs structures will also be studied. Based on the findings, the dependence of photo stability on SiQDs structures will be verified by parallel investigation on a series of structure modified SiQDs and their photo stability. Therefore, the ideal structure model for SiQDs with high photo stability will be presented, which assist us in structural design for novel SiQDs development.