Titanium Dioxide Nanomaterials: Synthesis, Properties, Modifications, and Applications

In this critical review, metal oxides-based materials for electrochemical supercapacitor (ES) electrodes are reviewed in detail together with a brief review of carbon materials and conducting polymers. Their advantages, disadvantages, and performance in ES electrodes are discussed through extensive analysis of the literature, and new trends in material development are also reviewed. Two important future research directions are indicated and summarized, based on results published in the literature: the development of composite and nanostructured ES materials to overcome the major challenge posed by the low energy density of ES (476 references).

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A review of electrode materials for electrochemical supercapacitors

2.3. Evaluation of Photocatalytic Water Splitting 6507 2.3.1. Photocatalytic Activity 6507 2.3.2. Photocatalytic Stability 6507 3. UV-Active Photocatalysts for Water Splitting 6507 3.1. d0 Metal Oxide Photocatalyts 6507 3.1.1. Ti-, Zr-Based Oxides 6507 3.1.2. Nb-, Ta-Based Oxides 6514 3.1.3. W-, Mo-Based Oxides 6517 3.1.4. Other d0 Metal Oxides 6518 3.2. d10 Metal Oxide Photocatalyts 6518 3.3. f0 Metal Oxide Photocatalysts 6518 3.4. Nonoxide Photocatalysts 6518 4. Approaches to Modifying the Electronic Band Structure for Visible-Light Harvesting 6519

Semiconductor-based Photocatalytic Hydrogen Generation

This review aims at reporting on very recent developments in syntheses, properties and (future) applications of polymer-layered silicate nanocomposites. This new type of materials, based on smectite clays usually rendered hydrophobic through ionic exchange of the sodium interlayer cation with an onium cation, may be prepared via various synthetic routes comprising exfoliation adsorption, in situ intercalative polymerization and melt intercalation. The whole range of polymer matrices is covered, i.e. thermoplastics, thermosets and elastomers. Two types of structure may be obtained, namely intercalated nanocomposites where the polymer chains are sandwiched in between silicate layers and exfoliated nanocomposites where the separated, individual silicate layers are more or less uniformly dispersed in the polymer matrix. This new family of materials exhibits enhanced properties at very low filler level, usually inferior to 5 wt.%, such as increased Young’s modulus and storage modulus, increase in thermal stability and gas barrier properties and good flame retardancy.

Polymer-layered silicate nanocomposites: preparation, properties and uses of a new class of materials

As a fascinating conjugated polymer, graphitic carbon nitride (g-C3N4) has become a new research hotspot and drawn broad interdisciplinary attention as a metal-free and visible-light-responsive photocatalyst in the arena of solar energy conversion and environmental remediation. This is due to its appealing electronic band structure, high physicochemical stability, and “earth-abundant” nature. This critical review summarizes a panorama of the latest progress related to the design and construction of pristine g-C3N4 and g-C3N4-based nanocomposites, including (1) nanoarchitecture design of bare g-C3N4, such as hard and soft templating approaches, supramolecular preorganization assembly, exfoliation, and template-free synthesis routes, (2) functionalization of g-C3N4 at an atomic level (elemental doping) and molecular level (copolymerization), and (3) modification of g-C3N4 with well-matched energy levels of another semiconductor or a metal as a cocatalyst to form heterojunction nanostructures. The constructi...

Graphitic Carbon Nitride (g-C3N4)-Based Photocatalysts for Artificial Photosynthesis and Environmental Remediation: Are We a Step Closer To Achieving Sustainability?

Cubic and Hexagonal Mesostructured Hexarhenium Selenocyanides: Supramolecular Assemblies of Octahedral Nanoclusters

The effects of bond covalency on the chemical bonding nature and lattice stability of ferroelectric bismuth-based transition-metal oxides have been investigated systematically through comparative X-ray absorption spectroscopic studies for several Aurivillius-structured materials and their chemically reduced derivatives. According to Ti K-edge X-ray absorption near-edge structure (XANES) analysis, Bi3TaTiO9 shows a weaker strength of (TiIV−O) bonds than Bi4Ti3O12, which could be interpreted as a result of the bond competition with highly covalent (TaV−O) bonds. Also, it was found that a lithiation process gives rise to a remarkable variation of Ti local structure commonly for Bi3TaTiO9 and Bi4Ti3O12. In contrast, there is only a slight spectral change in the Ta LIII-edge XANES spectra of Bi3TaTiO9 and SrBi2Ta2O9 upon the chemical reduction, underscoring the higher stability of more covalent (TaV−O) bonds than (TiIV−O) bonds. Alternatively, an energy difference between the peaks corresponding to Ta 2p3/2 → ...

Effect of Bond Covalency on the Lattice Stability and Fatigue Behavior of Ferroelectric Bismuth Transition-Metal Oxides

Mesoporous assembly of 2D manganate nanosheets intercalated with cobalt ions

High-Tc superconducting thin film from bismuth cuprate nano-colloids

Effects of synthesis temperature and precursor composition on the crystal structure, morphology, and electrode activity of 1D nanostructured manganese oxides

Seong Ju Hwang

Papers

Cubic and Hexagonal Mesostructured Hexarhenium Selenocyanides: Supramolecular Assemblies of Octahedral Nanoclusters

Effect of Bond Covalency on the Lattice Stability and Fatigue Behavior of Ferroelectric Bismuth Transition-Metal Oxides

Mesoporous assembly of 2D manganate nanosheets intercalated with cobalt ions

High-Tc superconducting thin film from bismuth cuprate nano-colloids

Effects of synthesis temperature and precursor composition on the crystal structure, morphology, and electrode activity of 1D nanostructured manganese oxides