title: Singlet oxygen production upon two-photon excitation of TiO2 in chloroform.
abstract: Singlet oxygen ((1)O(2)) signals observed upon illumination at 532 nm are a consequence of TiO(2) excitation in a two-photon process, and at 355 nm in a one-photon pathway. After corrections for light reflectance, the relative quantum yields of (1)O(2) production are 0.23+/-0.01 and 0.22+/-0.02 for 532 and 355 nm excitation, respectively. Total quenching rate constants of (1)O(2) removal by TiO(2) particles are near the diffusion-controlled rate limit. By employing (1)O(2) as a probe, we have established an efficient and simple method to elucidate the nature of TiO(2) photoexcitation.
authors: Department of Chemistry, Jackson State University, 1400 J. R. Lynch street, Jackson, MS 39217, USA.
authors: Wenbing
authors: W
authors: Li
authors: Naveen
authors: N
authors: Gandra
authors: Shavelle N
authors: SN
authors: Courtney
authors: Ruomei
authors: R
authors: Gao
mesh_terms: D002725:Chloroform / Q000737:chemistry; D008163:Luminescent Measurements; D010777:Photochemistry; D017785:Photons; D026082:Singlet Oxygen / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D026082:Singlet Oxygen; D002725:Chloroform; D014025:Titanium