硫化物/贵金属核壳结构光热转换材料的调控合成及其光热转换增强机制研究

Sulfide-noble metal core-hell structure materials have significant photothermal conversion enhancement effect and thus have promising applications in the photothermal therapy of tumor sells. However, the current lack of photothermal conversion enhancement mechanism hinders the theoretic research and development of sulfide-noble metal core-shell structure photothermal conversion materials. In this project, core-shell structure photothermal conversion materials of different composition and shell thickness are synthesized through an active template-interfacial reaction method, with core-shell structures made up of sulfides and noble metals including Ag and Au as research object. The influences of composition and shell thickness on the photothermal properties of the core-shell structures are investigated. The conversion of light energy to heat energy and other energy forms, as well as energy distribution and mutual growth and decline between different energy forms, are studied based on the principle of energy conservation. The generation and energy transform mechanism of the photo-generated carriers in the core-shell structures are studied by combining the related theories including metal surface plasmon resonance effect theory and electron band-structure theory. The coupling enhancement effects on the interface of the core-shell structures are emphatically studied. To reveal the scientific problem of the mechanism for photothermal conversion enhancement of the sulfide-noble metal core-shell structures based on the systematic study of photothermal conversion property is of theoretical and practical significance for the research and development of new photothermal conversion material.

硫化物/贵金属核壳结构材料对光热转换具有显著的增强作用，在肿瘤的光热治疗方面具有良好的应用前景。但目前缺乏对硫化物/贵金属核壳结构材料光热转换增强机制这一科学问题的研究，阻碍了硫化物/贵金属核壳结构光热转换材料的理论研究及应用开发。为此，本项目以硫化物和贵金属金、银组成的核壳结构为研究对象，采用活性模板法调控合成具有不同组成及壳厚的核壳结构光热转换材料，并研究组成及壳厚等因素对光热转换特性的影响规律；基于能量守恒原则，研究光能向热能及其他形式能量转化的能量分配以及相互消长的规律；结合金属表面等离子体共振效应和电子能带结构等相关理论，探讨硫化物/贵金属核壳结构中光生载流子的产生及能量转换机制，着重研究核壳界面处发生的相互作用及耦合增强效应；通过实验研究和理论计算结合，揭示硫化物/贵金属核壳结构材料的光热转换增强机制这一科学问题，对光热转换新材料的研究开发具有重要的理论和实际意义。

贵金属和相应的硫化物组成的核壳结构对光热转换具有显著的增强作用，在肿瘤的光热治疗方面具有良好的应用前景，研究此类材料的光热转换增强机制对肿瘤光热治疗材料的开发有重要意义。为此，本项目制备了一系列由Ag、Pd及其硫化物组成的核壳结构、壳层结构、异质结构等，研究了光热转换性能的影响因素、变化规律及增强机制，发现其光热转换性能均有显著增强。结合实验结果，通过理论模拟和理论分析发现核壳界面和异质界面是光热特性增强的主要因素，在一定的范围内，核壳结构的光热特性会随着壳厚的增加而增强。本项目还制备并研究了一系列宽频响应的光热转换材料以及适用于淋巴癌的磁成像-光热治疗双功能纳米材料。本项目的研究成果对开发光热治疗用核壳结构材料有指导意义，所制备的材料不仅可以应用于生物医疗领域，还可以拓展到太阳能光热利用领域。