2D/2D异质结构组装体的表界面调控与高效制氢机制研究

Photocatalytic hydrogen production technology provides an important way for human to realize the dream of using solar energy to obtain hydrogen energy directly from water. The project presents a new strategy for surface/interface regulation and efficient hydrogen production of g-C3N4/TiO2 2D heterostructure assemblies. Novel photocatalytic materials were constructed by designing the superaerophibic surface/interfaces and aming at the key of the design and precision preparation of the microstructure of the g-C3N4 and TiO2 2D building blocks. A scheme was proposed for 2D oriented growth induced by 2D crystal surface and the following self-assembly. Surface/interface regulation and effective coupling between 2D/2D heterostructures with lattice mismatch were realized. And new photocatalytic materials were invented. .The microstructures of the 2D building blocks were finely adjusted to reveal the regulation mechanism of the band structure and active sites distribution of photocatalysts, to study the features of suface/interface design benefiting H2 bubble growth and desorption escape, and to synergistically enhance the photocatalytic water splitting activity for hydrogen production. Combined with density functional theory calculation results, the structure-activity relationship of can be established for design-precise preparation-structure-performance integration of the photocatalyst materials, the mechanism of high efficient hydrogen production of 2D/2D heterostructure photocatalysts can be clarified, and multi-functional integration of g-C3N4/TiO2 photocatalysts can be realized. The research results will provide theoretical basis for the development and application of new energy photocatalytic materials.

光催化分解水制氢技术为人类实现利用太阳能直接从水中获得氢能源这一梦想提供了一条重要途径。本申请提出 2D/2D g-C3N4/TiO2异质结构组装体光催化材料的表界面调控与高效制氢研究新策略，瞄准g-C3N4和TiO2 2D构建单元表界面微观结构的设计与精准制备这一关键，设计具有“超疏气”性质的表界面，提出2D晶面诱导取向生长机理，实现2D/2D晶格失配异质结间的表界面调控及有效耦合，创制新型光催化材料。通过精细调控二维纳米构建单元的表界面微观结构，揭示光催化剂的能带结构和活性位点分布调控机制，研究有利于H2气泡生长和脱附逸出的表界面设计特征，协同提高光解水制氢活性。结合密度泛函理论计算，建立光催化材料设计-精准制备-结构-性能一体化的构效关系，阐明2D/2D异质结构光催化剂高效制氢机理，实现g-C3N4/TiO2光催化剂的多功能集成，为新能源光催化材料的开发与应用提供理论基础。

由太阳能驱动直接从水中制备H2绿色能源为工业应用带来了巨大的希望，H2的高效产出依赖于合理设计和精准制备高效、稳定的分级结构光催化剂。基于此，本研究首先聚焦g-C3N4/TiO2异质结构组装体光催化剂的表界面调控与高效制氢机制研究，发展了前驱体形貌拓扑转化制备g-C3N4/TiO2多级组装结构的新方法，实现g-C3N4的制备和负载一步完成，考察了前驱体的类型和热解方式对g-C3N4超薄纳米片形态结构的影响，系统研究了各种试验条件对TiO2前驱体的成核方式和晶体生长习性的调控规律，实现g-C3N4和TiO2构建单元尺寸、厚度、微观结构的调控与精准制备，建立起不同微结构g-C3N4/TiO2复合光催化材料精准制备的一系列新技术、新方法。发展了热解富含N的有机前驱体过渡金属氯化物深度共晶溶剂（DES）策略，建立了大量制备N掺杂碳、氧化石墨烯碳等2D碳材料复合光催化剂的新方法，发展了构建超亲水-超疏气表面性能催化材料新方法。提出了一种Cu2+离子吸附-还原策略来构建介孔Z机制型Cu2O/TiO2复合光催化剂来分解水/海水制氢；建立了氧化石墨烯包覆的富含硫空位暴露高指数晶面的Cd1-xZnxS固溶体多面体复合材料及其制备方法，为设计和构建高效稳定的海水制氢光催化剂提供了一种有效的解决方案。考察了材料表/界面性质对光谱吸收范围、能带结构和光催化反应活性的影响，对表/界面性质的调控所产生的新催化活性机理进行研究，初步总结了分级结构催化材料组成-分级结构-表界面性质-光催化产氢活性之间的相互关系。