Single-Crystalline Anatase TiO₂ Dous Assembled Micro-Sphere and Their Photocatalytic Activity

Abstract

Using anodized TiO 2 nanotubes as the starting materials, unique structural single-crystalline anatase TiO 2 dous assembled microspheres are fabricated by a hydrothermal method. The single-crystalline anatase TiO 2 dou is formed through the transformation of a TiO 2 nanotube, which is formed through a complex process including the expansion of the nanotube, dissolution-recrystallization, and recombination. The opening and hollow structural dou exposes one {001} face and eight {101} faces, which displays excellent photocatalytic activity. And it is also envisaged to be of high promise for many other potential applications. The approach might be exploited for the synthesis of single-crystalline nanomaterials with special morphologies.

Facile Fabrication of Anatase TiO2 Microspheres on Solid Substrates and Surface Crystal Facet Transformation from {001} to {101}

“…[5,22] The corresponding high-resolution TEM (HRTEM) image (bottom inset in Figure 3 a) shows the perpendicular lattice spacing of 0.19 nm representing the (200) and (020) atomic planes of the anatase TiO 2 , further confirmed exposed crystal facet is indeed the {001} facet. [5,22] This is in agreement with the studies by Hu et al and Liu et al [29,30] It should be noted that the above data was obtained from the samples obtained after ultrasonic treatment. [29,31] For the sample with 3 h reaction time, the SAED pattern (top inset in that the lateral facet is a single crystal.…”

“…[5,22] This is in agreement with the studies by Hu et al and Liu et al [29,30] It should be noted that the above data was obtained from the samples obtained after ultrasonic treatment. [29,31] For the sample with 3 h reaction time, the SAED pattern (top inset in that the lateral facet is a single crystal. HRTEM shows clear crystalline lattice fringes of the lateral facet.…”

Rapid anodic oxidation of highly ordered TiO2 nanotube arrays

“…And the fourth synthesis stage was achieved by nonfluoride-based anodization electrolyte [20,21]. To the best of our knowledge, during these four synthesis stages of TiO 2 nanotube arrays, the reaction time of anodization generally lasts 6-12 h, as in our previous work [22][23][24], and even longer when synthesizing thicker nanotubular layers [19,25]. To understand the slow growth of nanotubes during the anodization, the chemical dissolution related to the acidification of the electrolyte ought to be firstly taken into account [14,26].…”

“…In previous work the length of TiO 2 nanotubes has been recognized as the equilibria of the electrochemical formation of TiO 2 at the pore tip and the chemical dissolution of the formed TiO 2 by fluorides at the mouth of the tubes (nanotube arrays surface) in the F − -containing electrolyte [13][14][15][16][22][23][24][25][26], shown as Eqs. (1) and (2): …”

Synthesis of Ag-decorated porous TiO2 nanowires through a sunlight induced reduction method and its enhanced photocatalytic activity

“…Titanium dioxide (TiO 2 ), as a well-known photocatalyst with excellent photo-induced activity, has been extensively investigated in the past years [6][7][8][9][10][11]. However, the low surface area and quick recombination of photo-induced electron-hole pairs hinder the application of the commercial TiO 2 photocatalysts [12].…”