Allen J. Bard

Bio: Allen J. Bard is an academic researcher from University of Texas at Austin. The author has contributed to research in topics: Radical ion & Electrode. The author has an hindex of 30, co-authored 62 publications receiving 4821 citations.

Heterogeneous photocatalytic oxidation of cyanide and sulfite in aqueous solutions at semiconductor powders

Abstract: Suggesting that there are at least two kinds of metal-C0 bonds involved which undoubtedly have different bond energies and that their approximate ratio is 5/1, the type of site greatest in quantity being that which bonds most strongly with CO. There may be other types of sites or these two kinds may actually include subtypes which have bond energies so close as to be indistinguishable by this experimental technique. Since the room temperature rate constant for displacement for process I is about 7 times greater than that for process 11, the activation energy for process I1 must be 1200 cal greater than that for process I. This suggests that the CO displaced in process I1 might be bonded to the metal 1200 cal more strongly than that which is displaced

Semiconductor Electrodes: X . Photoelectrochemical Behavior of Several Polycrystalline Metal Oxide Electrodes in Aqueous Solutions

Abstract: An investigation was made of the photoelectrochemical properties of several polycrystalline metal oxide electrodes prepared by chemical vapor deposition, direct oxidation of the metal or heating of suitable metal salt solutions. Further data are given on the behavior of the previously discussed TiO/sub 2/ and Fe/sub 2/O/sub 3/ electrodes including tunneling effects and the operation of the Fe/sub 2/O/sub 3/ in a solar cell. Other n-type materials studied were V/sub 2/O/sub 5/, WO/sub 3/, and PbO. WO/sub 3/ and PbO showed good anodic photocurrents but only WO/sub 3/ appeared stable. Bi/sub 2/O/sub 3/ showed both n- and p-type photocurrents, but had a poor stability. CuO produced a good cathodic photocurrent (indicating p-type behavior) with a photoresponse at wavelengths of 700 nm and below. Two other oxides, Cr/sub 2/O/sub 3/ and CoO, exhibited small p-type photoeffects.

Heterogeneous photocatalytic synthesis of methane from acetic acid: new Kolbe reaction pathway

Abstract: The heterogeneous photocatalytic decomposition of acetic acid on n-type TiO/sub 2/ to yield almost exclusively methane and carbon dioxide is reported. Probable reaction mechanisms are discussed. It is assumed that the TiO/sub 2/ powder acts in a dual function causing the photooxidation of acetate and the reduction of intermediately formed methyl radicals. This property is not found at metal electrodes under usual Kolbe conditions. (JSR)

A metal-free polymeric photocatalyst for hydrogen production from water under visible light

Abstract: The production of hydrogen from water using a catalyst and solar energy is an ideal future energy source, independent of fossil reserves. For an economical use of water and solar energy, catalysts that are sufficiently efficient, stable, inexpensive and capable of harvesting light are required. Here, we show that an abundant material, polymeric carbon nitride, can produce hydrogen from water under visible-light irradiation in the presence of a sacrificial donor. Contrary to other conducting polymer semiconductors, carbon nitride is chemically and thermally stable and does not rely on complicated device manufacturing. The results represent an important first step towards photosynthesis in general where artificial conjugated polymer semiconductors can be used as energy transducers.

Solar Water Splitting Cells

Abstract: Energy harvested directly from sunlight offers a desirable approach toward fulfilling, with minimal environmental impact, the need for clean energy. Solar energy is a decentralized and inexhaustible natural resource, with the magnitude of the available solar power striking the earth’s surface at any one instant equal to 130 million 500 MW power plants.1 However, several important goals need to be met to fully utilize solar energy for the global energy demand. First, the means for solar energy conversion, storage, and distribution should be environmentally benign, i.e. protecting ecosystems instead of steadily weakening them. The next important goal is to provide a stable, constant energy flux. Due to the daily and seasonal variability in renewable energy sources such as sunlight, energy harvested from the sun needs to be efficiently converted into chemical fuel that can be stored, transported, and used upon demand. The biggest challenge is whether or not these goals can be met in a costeffective way on the terawatt scale.2

Titanium dioxide photocatalysis

Abstract: Scientific studies on photocatalysis started about two and a half decades ago. Titanium dioxide (TiO 2 ), which is one of the most basic materials in our daily life, has emerged as an excellent photocatalyst material for environmental purification. In this review, current progress in the area of TiO 2 photocatalysis, mainly photocatalytic air purification, sterilization and cancer therapy are discussed together with some fundamental aspects. A novel photoinduced superhydrophilic phenomenon involving TiO 2 and its applications are presented.

Titanium dioxide as photocatalysis

Abstract: Abstract Scientific studies on photocatalysis started about two and a half decades ago. Titanium dioxide (TiO 2 ), which is one of the most basic materials in our daily life, has emerged as an excellent photocatalyst material for environmental purification. In this review, current progress in the area of TiO 2 photocatalysis, mainly photocatalytic air purification, sterilization and cancer therapy are discussed together with some fundamental aspects. A novel photoinduced superhydrophilic phenomenon involving TiO 2 and its applications are presented.