Sustainable solar energy conversion with defined ferrite nanostructures

具有明确铁氧体纳米结构的可持续太阳能转换

• 批准号: 279037452
• 负责人: Professor Dr. Roland Marschall
• 金额: --
• 依托单位: Lehrstuhl für Physikalische Chemie III
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/279037452?language=en
• 关键词: Sustainable; solar; energy; conversion; defined

Photocatalysis and photoelectrochemistry with semiconductor materials is an important method for the sustainable utilization of sunlight for chemical reactions. Both methods are especially used in the degradation of recent environmental impacts like greenhouse gases and pollutants, and also for securing the future energy needs. Especially research regarding the photocatalytic and photoelectrochemical splitting of water has been intensified in recent years. However, it can be observed that research has mainly focused on binary oxides like TiO2, WO3 und a-Fe2O3, which however have major drawbacks (too large band gap, low charge carrier lifetimes) to find industrial application for water splitting. The task for materials scientists is now to increase the materials library for water splitting, and to find alternatives in ternary or quaternary oxide materials. Moreover, no expensive but earth-abundant element should comprise those materials, to keep the costs for sustainable hydrogen low.The given project focuses on the investigation of the properties of ternary spinel-type ferrites (MFe2O4) for photocatalytic and photoelectrochemical water splitting. The aimed materials consist only of earth-abundant elements (Ca, Mg, Fe, Zn, O), absorb to a large extend visible light (maximum band gap 2.2 eV), and are therefore theoretically able to reach more than 10% solar-to-hydrogen efficiency. The diffusion properties and lifetimes of charge carriers in these ferrites will be investigated, as well as the influence of nanostructuring on the properties of ferrite photoelectrodes. Both dense and mesoporous ferrite photoelectrodes will be prepared, by using both molecular and nanoparticular building blocks. Block-copolymers will be used as templates for the preparation of ordered mesoporous photoelectrodes via dip-coating.Finally, a self-sustaining tandem cell is targeted, by using both n- and p-type ferrites for the respective half reaction, to achieve spatially separated evolution of hydrogen and oxygen. To increase light absorption, deposition of ferrite thin films onto doped silicon wafers is targeted, to prepare monolithic p-n-heterojunction tandem photoelectrodes.

半导体材料的光催化和光电化学是可持续利用化学反应的阳光的重要方法。这两种方法都尤其用于降解最近的环境影响，例如温室气体和污染物，也用于确保未来的能源需求。近年来，有关水的光催化和光电化学分裂的研究尤其是研究。但是，可以观察到的研究主要集中在TiO2，WO3 und A-FE2O3等二元氧化物上，但是它们具有主要缺点（太大的带隙，低电荷载体寿命），以找到用于水分的工业应用。材料科学家的任务现在是增加材料库进行水分解，并在三元或第四纪氧化物材料中找到替代品。此外，没有昂贵的土壤含量应包含这些材料，以保持可持续氢的成本低。给定的项目着重于研究三元尖晶石型铁氧体（MFE2O4）用于光催化和光催化性和光电化学化学化学水的特性。瞄准的材料仅由土壤丰富的元素（Ca，Mg，Fe，Zn，O）组成，吸收到大延伸可见光（最大带隙2.2 eV），因此从理论上讲可以达到超过10％的太阳能到Hydrogen效率。将研究这些铁氧体中电荷载体的扩散特性和寿命，以及纳米结构对铁素体光电丝体性质的影响。通过使用分子和纳米关节构建块，将制备致密和介孔的光电电极。块聚合物将用作模板，以通过浸入涂层来制备有序的介孔光电极。在本文中，通过使用n-和p型的铁矿来实现自我维持的串联细胞，以实现N-和P型铁矿进行相应的半反应，以实现氢和牛的空间分离的氢和牛的空间分离。为了增加光吸收，将铁氧体薄膜沉积到掺杂的硅晶状体上，以制备单片P-N型结构结的光电电极。