Zindrou Areti, Psathas Pavlos, Deligiannakis Yiannis
Laboratory of Physical Chemistry of Materials & Environment, Department of Physics, University of Ioannina, 45110 Ioannina, Greece.
Nanomaterials (Basel). 2024 Feb 11;14(4):346. doi: 10.3390/nano14040346.
Engineering of oxygen vacancies (Vo) in nanomaterials allows diligent control of their physicochemical properties. SrTiO possesses the typical ABO structure and has attracted considerable attention among the titanates due to its chemical stability and its high conduction band energy. This has resulted in its extensive use in photocatalytic energy-related processes, among others. Herein, we introduce the use of Flame Spray Pyrolysis (FSP); an industrial and scalable process to produce Vo-rich SrTiO perovskites. We present two types of Anoxic Flame Spray Pyrolysis (A-FSP) technologies using CH gas as a reducing source: Radial A-FSP (RA-FSP); and Axial A-FSP (AA-FSP). These are used for the control engineering of oxygen vacancies in the SrTiO nanolattice. Based on X-ray photoelectron spectroscopy, Raman and thermogravimetry-differential thermal analysis, we discuss the role and the amount of the Vos in the so-produced nano-SrTiO, correlating the properties of the nanolattice and energy-band structure of the SrTiO. The present work further corroborates the versatility of FSP as a synthetic process and the potential future application of this process to engineer photocatalysts with oxygen vacancies in quantities that can be measured in kilograms.
纳米材料中氧空位(Vo)的工程化能够精确控制其物理化学性质。SrTiO具有典型的ABO结构,因其化学稳定性和高导带能量而在钛酸盐中备受关注。这使其在光催化能量相关过程等方面得到广泛应用。在此,我们介绍火焰喷雾热解(FSP)的应用;这是一种用于生产富含Vo的SrTiO钙钛矿的工业规模可扩展工艺。我们展示了两种以CH气体作为还原源的缺氧火焰喷雾热解(A-FSP)技术:径向A-FSP(RA-FSP)和轴向A-FSP(AA-FSP)。这些技术用于SrTiO纳米晶格中氧空位的控制工程。基于X射线光电子能谱、拉曼光谱和热重-差热分析,我们讨论了所制备的纳米SrTiO中Vo的作用和数量,将纳米晶格的性质与SrTiO的能带结构相关联。本工作进一步证实了FSP作为一种合成工艺的多功能性,以及该工艺未来在工程化制备千克级可测量数量的具有氧空位的光催化剂方面的潜在应用。