Mixed perovskite- and mullite-type bandgap tailored visible light photocatalysts for wastewater purification

用于废水净化的混合钙钛矿型和莫来石型带隙定制可见光光催化剂

• 批准号: 461295486
• 负责人: Professor Dr. Thorsten Michael Gesing
• 金额: --
• 依托单位: Arbeitsgruppe Neurobiochemistry
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/461295486?language=en
• 关键词: Mixed; perovskite; mullite; type; bandgap

The proposed project optimizes narrow bandgap materials for enhanced photocatalytic activity by using a combination of perovskite- and mullite-type compounds. Perovskite-type BiFeO3 and mullite-type Bi2Fe4O9 structures exhibit both high photocatalytic activities and oxidize organic pollutants, as in wastewater, into carbon dioxide and mineral acids under visible light irradiation. It is possible to substitute Fe3+ with other cations like Al3+, Ga3+ and Mn3+, also showing photocatalytic activity. Therefore, it bears a critical importance to investigate the rich set of solid solutions, by replacing the M-cations (M = Al3+, Ga3+, Mn3+) systematically, to establish a relation between composition, bandgap and the highest possible photocatalytic activity. The materials to be investigated are mainly Bi2M4O9 structures but explorative work on the Bi2Mn4O10 structure and related structures/compositions are as well planned. Our recent experiments showed that designing quantum-sized crystallites led to a co-crystallization of metastable (Bi1-xFex)FeO3 and Bi2Fe4O9. This finding offers the possibility to form two different photocatalytic active structures within one matrix leading to pseudo-single exciton stabilization analogous to that of well-known TiO2 rutile/anatase mixture. Using different synthesis routes such as the glycerin method, polyol method, PVA method and the flame spray pyrolysis different particle sizes, crystallite sizes as well as morphologies and perovskite-/mullite-type ratios could be produced. The materials will be characterized by diffuse reflectance UV/Vis spectroscopy, X-ray powder diffraction (XRPD), infrared (IR) and Raman spectroscopy, dynamic light scattering (DLS), small angle X-ray scattering (SAXS) and microscopic methods (TEM, SEM and EDX). For selected samples of good quality, the photocatalytic activity will be determined. For selected samples of good quality, the photocatalytic activity is determined, for which a corresponding flow cell is built and used as a test system. The resulting decomposition products are examined for their toxicity as well as by potential material abrasion.

拟议的项目通过结合钙钛矿和mullite型化合物来优化狭窄的带隙材料，以增强光催化活性。钙钛矿型BifeO3和Mullite型BI2FE4O9结构在可见光光照射下像废水一样表现出高光催化活性和氧化有机污染物，例如在废水中，进入二氧化碳和矿物质酸。也可以将Fe3+替换为Al3+，Ga3+和Mn3+的其他阳离子，也显示出光催化活性。因此，通过系统地替换M-cations（M = Al3+，Ga3+，Mn3+）来研究富集溶液的富溶液非常重要，以建立组成，带隙和最高可能的光催化活性之间的关系。要研究的材料主要是BI2M4O9结构，但是对BI2MN4O10结构和相关结构/组成的探索性工作也得到了很好的计划。我们最近的实验表明，设计量子大小的结晶石导致了亚固稳定（BI1-XFEX）FEO3和BI2FE4O9的共结晶。这一发现提供了在一个基质中形成两种不同的光催化活性结构的可能性，导致伪单个激子稳定稳定性类似于众所周知的TiO2金黄色葡萄球菌/剖析酶混合物。使用不同的合成途径，例如甘油方法，多元醇法，PVA方法和火焰喷射热解不同的粒径，可以产生晶体大小以及形态和钙钛矿 - /mullite型比率。材料的特征是弥漫性反射率紫外线光谱，X射线粉末衍射（XRPD），红外（IR）和拉曼光谱，动态光散射（DLS），小角度X射线散射（SAXS）和微观方法（SAXS）和微观方法（TEM，SEM，SEM和EDX）。对于质量良好的选定样品，将确定光催化活性。对于选定质量的样品，确定光催化活性，为其构建并用作测试系统。通过使用潜在的材料磨损来检查产生的分解产物。