Quantum yields of silver ion reduction on titanium dioxide and zinc oxide single crystals

Titania Photocatalysis beyond Recombination: A Critical Review

“…How is photocatalytic reaction kinetics described? The original idea for photocatalytic reaction kinetics was reported in 1972, the same year in which the above-discussed paper by Fujishima and Honda was published, by Fleischauer and coworkers [25]. As far as the author knows, this paper showed for the first time the effect of Langmuirian adsorption of a substrate on the rate (or quantum efficiency) of photocatalytic reaction by TiO 2 .…”

TiO2-based Photocatalysis: Surface Defects, Oxygen and Charge Transfer

“…After treatment, the crystal was subjected to XPS analysis where 2 N(1s) features were revealed, one at 396.5 eV (seen previously and assigned to substitutionally bound N ) ) and one at 399.6 eV, which we attribute to an N ÁÁÁ H complex interstitially bound in the TiO 2 lattice. A novel test, developed by Fleishauer et al [56] and used by others [57,58], was used to determine the photoactivity of the N ÁÁÁ H doped crystal as a function of photon energy, and the results yielded a significant decrease of 0.6 eV in the photothreshold energy needed for substrate excitation. The 2 feature XPS spectrum observed for the NH 3 treated samples is comparable to that presented by Asahi et al [54].…”

Revisiting the Original Works Related to Titania Photocatalysis: A Review of Papers in the Early Stage of Photocatalysis Studies

“…10 The present author considers this paper to be the first report on the effect of Langmuirian adsorption of a substrate on the rate (or quantum efficiency) of photocatalytic reaction by TiO 2 .…”

“…10 That paper was a valuable paper for the author since the author had no experience in photocatalytic reactions other than those producing hydrogen from aqueous solutions, presumably due to the trend of application of photocatalysis to energy conversion, i.e., water splitting, in those days. After studying the stoichiometry of reactions and the effects of pH of titania suspensions on the rate of reaction by titania suspended in aqueous silver salt solutions under photoirradiation, the author submitted a letter paper to a journal, but the paper was rejected because the phenomena and stoichiometry,…”

“…Before the works on photoinduced electron transfer in the 1960's and the beginning of the 1970's 13 cited in the above-mentioned paper, 10 there had been several reports on photoinduced metal deposition. According to the paper entitled "Reversible Photolysis of Ag Sorbed on Colloidal Metal Oxide" published in 1948, 14 Tammann reported in German in 1920 the photoinduced darkening of ZnO in aqueous solutions of silver salt such as silver nitrate and silver sulfate, 15 Kohlschuetter and d'Almendra repeated the experiments more carefully and found that the darkening was caused by deposition of metallic silver on the surface of metal oxide particles, 16 and then Perret showed that a saturated solution of silver ion by dissolving silver(I) oxide (Ag 2 O) also induced similar photoinduced darkening.…”