表面洁净金纳米线/3DOM-TiO2的可控构筑及表面等离子体光催化性能研究

Noble metal-semiconductor nanocomposites show wide application prospects such as new functional materials, new energy utilizations and environmental protections due to their unique optical, electrical and catalytic properties. These nanocomposites. So far, correlation researches mainly focus on the loading of zero and quasi-zero dimensional noble metal nanoparticles. However, as for the one dimensional Au nanowires (AuNWs) with special surface plasma properties, there has no report about the inter-coupling system of AuNWs nanostructures supported on semiconductors. The bottleneck problem is lacking of effective methods to construct the clean surfaces of the one dimensional nanowires/semiconductors composite materials. The applicant synthesized AuNWs of clean surface without using any organic template and broke through the limitations of traditional organic-template route. On this basis, an ideal semiconductor platform will be constructed for the oriented crystal growth of Au nanocrystals. We will explore the formation mechanism of surface-clean AuNWs through our novel controllable route on 3DOM-TiO2. Moreover, we will study the relationship between the photocatalytic performance and surface effect as well as interface state will be investigated based on the optimization process of the preparation route. A new kind of plasmon resonance-enhanced photocatalysts with clean surfaces and high energy conversion efficiencies are expected to be developed in this project.

贵金属-半导体复合纳米结构凭借独特的光、电及催化性质，在新功能材料、新能源利用及环境保护等重要领域表现出了广阔的应用前景。目前，相关研究主要集中在零维/准零维贵金属纳米粒子的负载，对于具有特殊表面等离子体共振效应的一维金纳米线（AuNWs）而言，其与半导体的相互耦合目前尚未见报道。其中关键的瓶颈问题在于如何实现一维贵金属/半导体材料洁净表面的高效构筑。申请人前期突破了传统有机模板路线的局限，首次无模板路线实现表面洁净AuNWs的制备。在此基础上，本项目拟通过3DOM-TiO2的结构调控，构建Au纳米晶定向生长的理想半导体平台，探索3DOM-TiO2表面负载洁净AuNWs的新合成路线，深入研究其合成规律、形成机理。本项目通过对AuNWs原位复合过程的优化，探讨AuNWs的表面效应、界面状态与光催化性能之间的关系，并可望开发一种表面洁净、具有高能量转换效率的新型表面等离子体光催化材料。

三维有序大孔二氧化钛（3DOM-TiO2）材料因具有较高的比表面积和特有的慢光子效应，从而表现出优于其他形貌TiO2的独特性能。为了解决3DOM-TiO2本身的能带结构造成了其光生电子与空穴易复合、可见光区域难以利用等固有缺陷，项目成员首先围绕3DOM-TiO2进行了大量的研究。其中，本研究创新地以离心力为控制因子，成功合成了窗口直径可控的3DOM-TiO2。本文以实验室制备的3DOM-TiO2作为载体，采用表面负载和体相掺杂两种改性路径，以碳氮层（NC）、二硫化钼（MoS2）、金纳米粒子（AuNPs）和硫化铜（CuS）材料作为改性物种，分别对3DOM-TiO2载体材料进行形貌调控并从光催化、电化学储能的方面出发，进行了性能研究并探索两者之间的构效关系。其次，基于一维细菌纤维素骨架构筑二维半导体材料及光催化性能研究。在不使用任何有机模板剂的情况下，本研究首次通过生物模板法将CdS担载在BC上，在三维交联结构中得到了形貌均一、孔结构丰富的二维CdS纳米片材料、SrTiO3、ZrTiO4一维半导体材料及光催化性能研究、多级结构的花球状半导体及其性能研究。