二氧化钛基纳米异质材料协同性能调控研究

TiO2-based nano heterojunctions can be used to expand the absorption spectrum, to separate electron and hole rapidly, to improve carrier transport properties and to enhance photoelectric conversion efficiency, so it is expected that these materials play an important role in the development of solar cell, visible light catalysis and hydrogen production field. This research intends to: prepare TiO2 nanostructures with the high specific surface area by hydrothermal method and acid and alkali oxidation; deposit transition metal oxides (XmOn) particles with different morphology and size distribution on the surface of TiO2 nanostructures by electrochemical deposition and chemical bath deposition and study the effect of XmOn on the nano heterojunction; explore the experimental conditions to prepare XmOn particles with more morphology and narrow size distribution and to minimize the carrier scattering of large XmOn particles; reduce the absorption, recombination and scattering of carrier in the interface for TiO2-based nano heterojunction, reveal effects of the size and size distribution for XmOn on nano heterojunction level distribution; explore the interactions and transmission mechanism of photo-induced charge with the heterostructure. On this basis, the association between the nano heterojunction and its properties will be summarized and the way to improve separation efficiency of the electron hole pairs will be explored.

二氧化钛基纳米异质结构可大幅拓展吸收光谱范围，实现电子和空穴快速分离，改善载流子输运特性，提高光电转换效率，有望在太阳能电池、可见光催化和制氢领域得到广泛应用，具有重要研究价值和广阔应用前景。本项目拟用水热法和酸碱氧化法制备高比表面积TiO2纳米结构；用电化学沉积技术和化学浴沉积法在TiO2纳米结构表面沉积不同形貌和粒径分布的过渡族金属氧化物XmOn颗粒，揭示XmOn颗粒对纳米异质结构性能的影响；通过优化实验参数，给出获得多形貌和窄粒径分布XmOn颗粒实验条件，减少大粒径XmOn对光的散射；解决TiO2基纳米异质结构中光生载流子在界面的吸收、复合和散射问题，研究XmOn尺寸和粒径分布对纳米异质结构能级分布的影响，探索光生电荷与异质结构的相互作用及传输机理。在此基础上，总结纳米异质结构设计与光电化学性能、光催化及制氢性能之间的关联，寻求提高电子空穴对分离效率的方法。

本项目对二氧化钛基纳米异质材料协同性能调控进行了科学凝练并开展研究。采用气相水热法和电化学法制备了高比表面积的TiO2纳米分级结构；用电化学沉积技术和化学浴沉积法在TiO2纳米分级结构表面沉积了过渡族金属氧化物XmOn量子点，研究了XmOn量子点对纳米异质结构性能的影响；通过优化实验参数，给出获得多形貌和窄粒径分布XmOn量子点实验条件，减少了大粒径XmOn对光的散射；降低了了TiO2基纳米异质结构中光生载流子在界面的吸收、复合和散射问题；研究了XmOn量子点尺寸和粒径分布对纳米异质结构能级分布的影响；探索了光生电荷与异质结构的相互作用及传输机理。在此基础上，总结了纳米异质结构设计与光电化学性能、光催化及制氢性能之间的关联。