New preparation method for doped polycrystalline TiO/sub 2/ and Nb/sub 2/O/sub 5/ and their photoelectrochemical properties

Journal Article · Thu Sep 02 04:00:00 EDT 1982 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100215a018· OSTI ID:6449833

Matsumoto, Y; Shimizu, T; Toyoda, A; Sato, E I

Doped polycrystalline TiO/sub 2/ and Nb/sub 2/O/sub 5/ have been prepared by a new method and examined as photoanodes. Polycrystalline oxide films on metal substrates which are thick and porous are prepared by anodic oxidation accompanied by sparking in various electrolytes. It was found that cations in the electrolyte are doped into the oxide films during anodic oxidation, which has been proved by ion microprob analysis and mass spectroscopy. Therefore, this is a new easy method of preparing doped polycrystalline TiO/sub 2/ and Nb/sub 2/O/sub 5/. The TiO/sub 2/ film prepared in Na/sub 2/SO/sub 4/ solution at 100 V is a good photoanode, showing a relatively high photocurrent under visible-light illumination. The doping is carried out by addition of the doping ions in saturated Na/sub 2/SO/sub 4/ solution. The Cr-, Ir- and Rh-doped TiO/sub 2/ films exhibit a high visible photocurrent but a low UV photocurrent. The Cr-doped Nb/sub 2/O/sub 5/ films also exhibit similar spectral responses. An increase in the UV photoresponse and a decrease in the visible photoresponse by reduction are observed. The relationship in which the band-gap photocurrents decrease with increasing visible photocurrents is obtained for the doped oxide films. This suggests, with the reduction effects, that the impurity and the interstitial metal d bands or states bringing about the visible response also act as recombination centers. 6 figures, 2 tables.

• Research Organization: Utsunomiya Univ., Japan
• OSTI ID: 6449833
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 86:18; ISSN JPCHA
• Country of Publication: United States
• Language: English

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ADDITIVES
ALKALI METAL COMPOUNDS
ANODES
CHALCOGENIDES
CHEMICAL PREPARATION
CHROMIUM
CRYSTAL DOPING
CRYSTALS
CURRENTS
DATA
DOPED MATERIALS
ELECTRIC CURRENTS
ELECTRODES
ELEMENTS
EXPERIMENTAL DATA
FILMS
INFORMATION
IRIDIUM
MASS SPECTRA
MATERIALS
METALS
NIOBIUM COMPOUNDS
NIOBIUM OXIDES
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PHOTOANODES
PHOTOCURRENTS
PLATINUM METALS
POLYCRYSTALS
RHODIUM
SODIUM COMPOUNDS
SODIUM SULFATES
SPECTRA
SULFATES
SULFUR COMPOUNDS
SYNTHESIS
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS