ALTHOUGH the possibility of water photolysis has been investigated by many workers, a useful method has only now been developed. Because water is transparent to visible light it cannot be decomposed directly, but only by radiation with wavelengths shorter than 190 nm (ref. 1).

Electrochemical Photolysis of Water at a Semiconductor Electrode

Although gold is the subject of one of the most ancient themes of investigation in science, its renaissance now leads to an exponentially increasing number of publications, especially in the context of emerging nanoscience and nanotechnology with nanoparticles and self-assembled monolayers (SAMs). We will limit the present review to gold nanoparticles (AuNPs), also called gold colloids. AuNPs are the most stable metal nanoparticles, and they present fascinating aspects such as their assembly of multiple types involving materials science, the behavior of the individual particles, size-related electronic, magnetic and optical properties (quantum size effect), and their applications to catalysis and biology. Their promises are in these fields as well as in the bottom-up approach of nanotechnology, and they will be key materials and building block in the 21st century. Whereas the extraction of gold started in the 5th millennium B.C. near Varna (Bulgaria) and reached 10 tons per year in Egypt around 1200-1300 B.C. when the marvelous statue of Touthankamon was constructed, it is probable that “soluble” gold appeared around the 5th or 4th century B.C. in Egypt and China. In antiquity, materials were used in an ecological sense for both aesthetic and curative purposes. Colloidal gold was used to make ruby glass 293 Chem. Rev. 2004, 104, 293−346

Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology.

To use solar irradiation or interior lighting efficiently, we sought a photocatalyst with high reactivity under visible light. Films and powders of TiO 2- x N x have revealed an improvement over titanium dioxide (TiO 2 ) under visible light (wavelength 2 has proven to be indispensable for band-gap narrowing and photocatalytic activity, as assessed by first-principles calculations and x-ray photoemission spectroscopy.

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Visible-Light Photocatalysis in Nitrogen-Doped Titanium Oxides

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

The surface science of titanium dioxide

The attractive behavior and advantages of a diamond electrode detector for a micromachined capillary electrophoresis (CE) system are discussed. A chemically vapor-deposited boron-doped diamond (BDD) film band (0.3 × 6.0 mm) electrode is used for end-column amperometric detection. The favorable performance of the diamond electrode microchip detector is indicated from comparison to a commonly used thick-film carbon detector. The diamond electrode offers enhanced sensitivity, lower noise levels, and sharper peaks for several groups of important analytes (nitroaromatic explosives, organophosphate nerve agents, phenols). The favorable signal-to-background characteristics of the BDD-based CE detector are coupled with a greatly improved resistance to surface fouling and greater isolation from high separation voltages. The enhanced stability is indicated from a RSD of 0.8% for 60 repetitive measurements of 5 ppm 2,4,6-trinitrotoluene (vs RSD of 10.8% at the thick-film carbon electrode). A highly linear response i...

Microchip Capillary Electrophoresis Coupled with a Boron-Doped Diamond Electrode-Based Electrochemical Detector

Tunable photonic band gap crystals were prepared by the infiltration of photoresponsive liquid crystals into inverse opal structure films. Tuning of their optical properties could be realized by means of photoinduced phase transition of liquid crystals. The photoinduced phase transition behavior could be evaluated by measuring the change in their optical properties under light irradiation, and it was clearly observed that the behavior varied with temperature and light intensity. The materials could store and display images that were created by the irradiation with UV light through a photomask. A great advantage of this technique is that the films themselves can display an image without the use of polarizers or other assistant materials, and they can also render a color display that can be selected by varying the lattice distance of the inverse opal structure. In addition, we achieved the control of their optical properties by the application of an electric field. Because the state induced by the electric ...

Control of the Optical Properties of Liquid Crystal-Infiltrated Inverse Opal Structures Using Photo Irradiation and/or an Electric Field

https://www.rsc.org/suppdata/CC/b9/b903284c/b903284c.pdf

Boron-doped diamond nanograss array for electrochemical sensors.

Study of carbon dioxide reduction at RuO2-coated diamond electrodes showed that conductive metallic oxides are promising electrocatalysts for this process and allow higher reduction products to be obtained. The main reduction products obtained in acidic and neutral media were formic acid and methanol, with product efficiencies as high as 40 and 7.7%, respectively. It was observed that conductive diamond is a very well suited material for studying the electrocatalytic properties of conductive metallic oxides, because its use resulted in a negligible substrate effect. This feature will greatly enhance the ability to understand the relationships between the intrinsic electrochemical behavior and the electrocatalytic behavior, in view of developing new effective electrocatalysts. The use of conductive diamond could also allow better utilization of the electrocatalyst by avoiding the need for thick films.

Akira Fujishima

Papers

Microchip Capillary Electrophoresis Coupled with a Boron-Doped Diamond Electrode-Based Electrochemical Detector

Control of the Optical Properties of Liquid Crystal-Infiltrated Inverse Opal Structures Using Photo Irradiation and/or an Electric Field

Boron-doped diamond nanograss array for electrochemical sensors.

Electrochemical reduction of carbon dioxide at ruthenium dioxide deposited on boron-doped diamond

Patterning of a Colloidal Crystal Film on a Modified Hydrophilic and Hydrophobic Surface