Exfoliation of one-dimensional TiO₅ chain in K₂TiO₃

Abstract

Potassium titanate, K 2 TiO 3 , with a chain structure of TiO 5 polyhedra was exfoliated in an aqueous nitric acid solution of pH ≤ 1 and Tyndall scattering due to the colloid formed by the exfoliation was observed. The colloidal particle size measured by dynamic light scattering was approximately 300 nm. Stripe pattern observed in transmission electron microscopy for the aggregated grains after their drying suggested the TiO 5 chains were exfoliated in acid solution. X-ray absorption showed that the coordination polyhedron around Ti 4+ changed from a square pyramid in K 2 TiO 3 powder to a distorted octahedron formed with the additional hydronium ions in the acidic solution.4

Hydrogen Titanate H2TiO3 Nanowires Derived from K2TiO3 as Potential Materials for Solar Cell Applications: A Theoretical Study

“…In this section we decided to work with an ASW cluster consistent with the crystal previously optimized via DFT using periodic boundary conditions. The ASW cluster has a size comparable with TEM images observed in the experimental work [4] . Figure 8 a) Presents the geometry optimization for the isolated ASW cluster, in order to conserve the stoichiometry, we decided to end the [TiO 5 ] chain with [TiO 4 ] coordinated polyhedrons.…”

Liquid exfoliation of five-coordinate layered titanate K2Ti2O5 single crystals in water

“…The yield could be potentially increased by changing the treatment conditions. To confirm the specificity of this reaction for the five-coordinated K 2 [5] Ti 2 O 5 crystal structure, we employed another layered titanate K 2 [6] hydrothermal/solvothermal conditions. The light-gray color of both images indicates the transmission of the electron beam, indicating significant exfoliation.…”

“…4 With respect to the production of TiO 2 -based 2D materials, several chemical techniques, such as the introduction of protons into interlayers and subsequent acid-base reactions with bulky organic bases such as tetrabutyl ammonium hydroxide (TBAOH) are required to exfoliate the parent layered metalates including titanates because the interlayer electrostatic interactions are strong. 5 In the case of K 2 [5] TiO 3 , which has a chain structure of TiO 5 polyhedra (here, " [5] " indicates the coordination number (CN) of Ti), 6 its immersion in an aqueous nitric acid solution at pH ≤ 1 leads to the formation of a colloidal suspension of nanosheets. Therefore, a fundamental question is whether the layered titanates can be exfoliated in eco-friendly solvents without the use of acids and bulky bases, as is the case for the exfoliation of transition metal dichalcogenides and Ca 2 N in common solvents such as N-methylpyrrolidone (NMP), 2-propanol, and 1,3-dioxane.…”

Developing new antiferroelectric and ferroelectric oxides and chalcogenides within the A2BX3 family

“…The known materials (K 2 PbO 3 , Rb 2 PbO 3 , K 2 TiS 3 , Cs 2 ZrSe 3 , etc.) are oxides, sulfides, and selenides that have already been synthesized and characterized using a variety of methods that include molten hydroxide fluxes [62], high-temperature ampule reactions [61], solid-state calcination [74], hydrothermal growth [75], and sol-gel reactions [73], and whose functional properties as FE and AFE materials has previously gone overlooked. The main goals of this study are to (a) develop methodology for future high-throughput studies, (b) more fully map out the potential energy landscape of antipolar and polar A 2 BX 3 compositions, (c) predict new semiconductive AFE and FE materials that are yet to be synthesized, and (d) investigate the effects of compositional tuning on known structures.…”