Application of Titanate Nanotubes for Photocatalytic Decontamination in Water: Challenges and Prospects

Abstract

Photocatalysis is an efficient technology for water decontamination and purification. Development of photocatalysts with high activity becomes the key to this research area. In recent years, titanate nanotubes (TNTs), derived from TiO2 nanoparticles through hydrothermal treatment with NaOH/KOH, have been attracting great attention. TNTs are composed of edge-sharing [TiO6] octahedrons as the skeleton and Na+/H+/K+ in the interlayers, which exhibit a uniform tubular microstructure, a large specific surface area, high photoelectric conversion properties, and good stability. Therefore, TNTs and their modified materials are widely used for removal of heavy metals and organic contaminants through photocatalytic oxidation or reduction. In this perspective, we systematically summarize cutting-edge research on the application of TNT-based photocatalysts in the water treatment area, illustrate the challenges for fundamental research and practical applications, and reveal the critical knowledge gaps and research needs for the future. In particular, preparation and specific properties of TNT-based photocatalysts are presented. Modification of TNTs to promote photocatalytic activity is discussed as well as their applications for contaminants removal from water. The latest advances in theoretical calculations on materials and contaminants in this photocatalysis system are clarified. In the future, strategic programs on both fundamental research and practical applications of TNT-based photocatalysts are proposed.

Operando Spectroscopic Observation of CO Oxidation on a Pt/TiO2 Catalyst in NO–CO Mixtures under Dark and UV Illumination

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Nanomaterial-Based Advanced Oxidation/Reduction Processes for the Degradation of PFAS

“…One dimensional titanate nanotubes (TNT) are TiO2 derivatives that have an uniform crystalline and scrolled tubular structure [TiO6], large SSA and high pore volume, good ion-exchange ability, high photoelectric conversion properties and, some derivatives, have high visible light response [86]. Figure 9 shows a scheme of the formation of TNT.…”

Tracking Coordination Environment and Reaction Intermediates in Homogeneous and Heterogeneous Epoxidation Catalysts via Ti L2,3-Edge Near-Edge X-ray Absorption Fine Structures

“…It has also been used to study oxygen vacancies in TiO 2 and the solid–liquid interface in TiO 2 /H 2 O systems . In contrast, Ti L 2,3 -edge NEXAFS has rarely been applied in molecular systems, − and the interpretation of the spectroscopic signatures has so far remained mostly empirical (by comparison with appropriate solid-state references) or in some cases aided by computation, notably to determine the structure of sodium titanate nanotubes (nonmolecular). , Recent work has extended this spectroscopic technique to studying Ti-based zeolites, where Ti atoms substitute specific positions of the crystalline lattice and has been proposed to highlight the presence of octahedral sites not readily accessible from K-edge XAS . However, understanding the origin of the observed transitions and their relation to the specific electronic structure remains an uncharted territory.…”