Semiconductor photocatalytic material and technology are of great significance in degradation of pollutant and conversion of solar energy. Among various oxide semiconductor photocatalysts, titania is the most important one up to now due to its chemical inertness, low price, nontoxicity, and strong oxidation and reduction ability under solar light. However, the photocatalytic performance of titania should be further improved from the viewpoint of practical application and commerce. To achieve this purpose, we invited investigators to contribute review and original research articles on TiO2 photocatalytic materials. This special issue consists of 19 papers, mainly related to environmental purification of TiO2 photocatalytic materials. Among them, 15 papers are about TiO2 photocatalytic materials. A brief summary of all 19 accepted papers is provided below.
In “Effect of Ce Doping on RGO-TiO2 Nanocomposite for High Photoelectrocatalytic Behavior,” the paper indicates that the Ce-doped RGO-TiO2 composite film showed higher photoelectrochemical performance than that of RGO-TiO2 composite and pure TiO2 under solar simulator irradiation.
The paper “Theoretical Study on Electronic Structure and Optical Performance of Nickel and Nitrogen Codoped Rutile Titanium Dioxide” reports ab initio calculations of nickel-doped, nitrogen-doped, and nickel + nitrogen-codoped rutile TiO2 based on density functional theory.
The paper “Application of Glass Fiber-Based N-Doped Titania under Visible-Light Exposure for Photocatalytic Degradation of Aromatic Pollutants” reports fabrication of flexible glass fiber-supported nitrogen-doped TiO2 photocatalysts by a dip-coating method followed by a low-temperature heat-treatment process and their application for the degradation of aromatic volatile organic compounds (VOCs) under visible-light irradiation.
The paper “Effects of UV-Vis Irradiation on Vanadium Etioporphyrins Extracted from Crude Oil and the Role of Nanostructured Titania” reports the use of N-TiO2/Cu induces an important delay in the initiation of the porphyrins’ photodegradation process.
The paper “Influence of Nd-Doping on Photocatalytic Properties of TiO2 Nanoparticles and Thin Film Coatings” reports structural, optical, and photocatalytic properties of TiO2 and TiO2:Nd nanopowders and thin films.
The paper “Effect of Aging Time and Film Thickness on the Photoelectrochemical Properties of TiO2 Sol-Gel Photoanodes” reports a nonaqueous based sol-gel process to produce TiO2 based photoelectrodes for solar water splitting.
The paper “Synthesis of Submicron Hexagonal Plate-Type SnS2 and Band Gap-Tuned Sn1−xTixS2 Materials and Their Hydrogen Production Abilities on Methanol/Water Photosplitting” reports SnS2 and Sn1−xTixS2 (x = 0, 0.1, 0.3, 0.5, and 0.7 mol) materials designed using solvothermal method with the aim of enhancing hydrogen production from water/methanol aqueous solution.
The paper “Role of Platinum Deposited on TiO2 in Photocatalytic Methanol Oxidation and Dehydrogenation Reactions” reports that the platinized titanium dioxide samples are always more active than the corresponding bare TiO2 for both methanol oxidation and dehydrogenation processes. The loading with various platinum amounts resulted in a significant improvement of the photocatalytic activity of TiO2. This beneficial effect was attributed to an increased separation of the photogenerated electron-hole charge carriers.
The paper “An Overview: Recent Development of Titanium Oxide Nanotubes as Photocatalyst for Dye Degradation” presents a critical review of recent achievements in the modification of TiO2 nanotubes for dye degradation.
The paper “TiO2 Nanotube Arrays Composite Film as Photoanode for High-Efficiency Dye-Sensitized Solar Cell” presents a double-layered photoanode made of hierarchical TiO2 nanotube arrays (TNT-arrays) as the overlayer and commercial-grade TiO2 nanoparticles (P25) as the underlayer for dye-sensitized solar cells (DSSCs).
The paper “Hole-Phonon Relaxation and Photocatalytic Properties of Titanium Dioxide and Zinc Oxide: First-Principles Approach” presents first-principles calculations for the temporal characteristics of hole-phonon relaxation in the valence band of titanium dioxide and zinc oxide.
The paper “Electronic Structures of S/C-Doped TiO2 Anatase (101) Surface: First-Principles Calculations” presents the electronic structures of sulfur- (S-) or carbon- (C-) doped TiO2 anatase (101) surfaces investigated by density functional theory (DFT) plane-wave pseudopotential method.
The paper “Synthesis and Photocatalytic Activity of Magnetically Recoverable Core-Shell Nanoparticles” presents TiO2/SiO2/Fe3O4 (TSF) core-shell nanoparticles with good photocatalytic activity and capable of fast magnetic separation after photocatalytic reaction.
The paper “Photocatalytic Bactericidal Efficiency of Ag Doped TiO2/Fe3O4 on Fish Pathogens under Visible Light” presents photocatalytic bactericidal efficiency of Ag-TiO2/Fe3O4 under visible light using target pollutants that include Aeromonas hydrophila, Edwardsiella tarda, and Photobacterium damselae subsp. piscicida.
The paper “Boundary Layer of Photon Absorption Applied to Heterogeneous Photocatalytic Solar Flat Plate Reactor Design” presents the design of heterogeneous photocatalytic solar reactors with flat plate geometry used in treatment of effluents and conversion of biomass to hydrogen.
The paper “Antimicrobial Activity of TiO2 Nanoparticle-Coated Film for Potential Food Packaging Applications” presents the antimicrobial activity of the films investigated by their capability to inactivate Escherichia coli (E. coli) in an actual food packaging application test under various conditions, including types of light and the exposed light time.
The paper “Preparation, Characterization, and Biotoxicity of Nanosized Doped ZnO Photocatalyst” presents preparation of five types of nondoped ZnO, iron-doped ZnO, cobalt-doped ZnO, nickel-doped ZnO, and manganese-doped ZnO materials by a wet chemical method, which were then exposed to Daphnia magna (D. magna) at low and high concentrations (50 and 250 μgL−1).
The paper “Manipulation of MWCNT Concentration in MWCNT/TiO2 Nanocomposite Thin Films for Dye-Sensitized Solar Cell” presents preparation of dye-sensitized solar cell (DSSC) using multiwalled carbon nanotube/titanium dioxide (MWCNT/TiO2) using sol-gel method.
The paper “Oxidation of 4-Chlorophenol by Mesoporous Titania: Effect of Surface Morphological Characteristics” presents preparation of mesoporous nanocrystalline anatase via EISA employing CTAB as structure directing agent.
Acknowledgment
We wish to express our sincere thanks to all the authors for submitting their articles to this special issue.
Jiaguo Yu
Mietek Jaroniec
Wei Xiao
Christos Trapalis
Hong Liu