Large Scale Synthesis and Gas-Sensing Properties of Anatase TiO₂ Three-Dimensional Hierarchical Nanostructures

Abstract

Three-dimensional (3D) crystalline anatase titanium dioxide (TiO(2)) hierarchical nanostructures were synthesized through a facile and controlled hydrothermal and after-annealing process. The formation mechanism for the anatase TiO(2) 3D hierarchical nanostructures was investigated in detail. The 3D hierarchical nanostructures morphologies are formed by self-organization of several tens of radially distributed thin petals with a thickness of several nanometers with a larger surface area. The surface area of TiO(2) hierarchical nanostructures determined by the Brunauer-Emmett-Teller (BET) adsorption isotherms was measured to be 64.8 m(2) g(-1). Gas sensing properties based on the hierarchical nanostructures were investigated. A systematic study on sensitivity as a function of temperatures and gas concentrations was carried out. It reveals an improved ethanol gas sensing response property with a sensitivity of about 6.4 at 350 degrees C upon exposure to 100 ppm ethanol vapor for the TiO(2) hierarchical nanostructures. A gas sensing mechanism based on the adsorption-desorption of oxygen on the surface of TiO(2) is discussed and analyzed. This novel gas sensor can be multifunctional and promising for practical applications. Furthermore, the hierarchical nanostructures with high surface area can find variety of potential applications such as solar cells, biosensors, catalysts, etc.

Hydrothermal synthesis of anatase flower‐like nanostructures for photocatalytic degradation of dye

“…Figure 2 shows the XRD patterns of flower-like nanostructures TiO 2 . The final white products are composed of anatase TiO 2 with lattice constants of a=3.785 Å and c = 9.514 Å, which are in good agreement with the literature value [14] [16,17], which is agreement with the result of XRD shown in figure 2. The forbidden-band width of the nano-TiO 2 is 3.2 eV, which corresponds to the energy of the photon at 387.5 nm.…”

“…Sample synthesis We synthesized the samples according to former study [14]. In a typical experiment, 50 mg of titanium powder was added to 70 mL of 10 M NaOH solution.…”

Study on growth rate of TiO2 nanostructured thin films: simulation by molecular dynamics approach and modeling by artificial neural network

“…This material has attained a great importance in several technological applications such as solar cells, [1][2][3] photo-catalyst, [4] sensors [5][6][7] and memory devices. [8] TiO 2 nanostructured thin films are also used as various optical coatings for its good transmittance in the visible region, high refractive index and chemical stability.…”

Fabrication of a 3D Hierarchical Flower‐Like MgO Microsphere and Its Application as Heterogeneous Catalyst

“…Luckily, the hydrothermal route [13] has probably provided us with a new idea for facile synthesis of 3D architectural structures in which ordered aggregates can form in a spontaneous process under these special condition. Up to now, significant efforts have been made to design and prepare 3D assembled nanostructures, by the hydrothermal route, such as NiO, [14] Fe 2 O 3 , [15] V 2 O 5 , [16] TiO 2 [17] etc. However, 3D hierarchical MgO has been little studied in the previous works.…”