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

A method for producing a porous diamond according to the present invention comprises steps of forming an anodized alumina layer, which functions as a mask, on a diamond substrate; and performing a plasma etching treatment to form pores on the diamond substrate, which pores have the same arrangement as those of the anodized alumina mask.

Method for producing porous diamond

Influence of direct current power on the photocatalytic activity of facing target sputtered TiO2 thin films

The photoelectrochemical behavior of chlorophyll (Chl) a and b monolayers, deposited on SnO/sub 2/ optically transparent electrodes by means of the Langmuir--Blodgett technique, has been investigated. Photocurrents and photovoltages were always anodic and negative, respectively, corresponding to an electron injection from excited Chl molecules to the conduction band of SnO/sub 2/. Spectra of photocurrents and photovoltages coincided well with the absorption spectra of Chl monolayers at the SnO/sub 2/-solution interface. Effects of light intensity, electrode potential, redox agents added, and solution pH on the magnitude of the photocurrent were studied in detail. The quantum efficiency for photocurrent generation was measured with Chl a--stearic acid mixed monolayers, and a highest value of 12 to 16% was attained at the Chl a/stearic acid molar ratio of ca. 1.0. The usefulness of the present system for an in vitro simulation of photosynthetic primary processes is suggested. 2 tables; 16 figures.

Light energy conversion with chlorophyll monolayer electrodes. in vitro electrochemical simulation of photosynthetic primary processes

Azobenzene-Derivative Langmuir-Blodgett Films Deposited on Various Thiol Monolayers

The photochromic responses of mixed WO3 – MoO3 thin films subjecting to UV irradiation were investigated in reducing environments, and they were compared with those of WO3 and MoO3 thin films. It was found that the photochromism of mixed 92% WO8% MoO3 thin film in ethanol vapor was significantly enhanced than that of WO3 or MoO3. The associated change in the absorbance (ΔABS) of the mixed-oxide film was about 1.5 times that of the WO3 film, and about 2.7 times that of the MoO3 film.

Akira Fujishima

Papers

Method for producing porous diamond

Influence of direct current power on the photocatalytic activity of facing target sputtered TiO2 thin films

Light energy conversion with chlorophyll monolayer electrodes. in vitro electrochemical simulation of photosynthetic primary processes

Azobenzene-Derivative Langmuir-Blodgett Films Deposited on Various Thiol Monolayers

Photochromic characteristics of mixed WO3-MoO3 thin films in alcohol vapors