Titanium dioxide photooxidation of thiocyanate. (SCN) sub 2 sup sm bullet minus studied by diffuse reflectance flash photolysis

Journal Article · Thu May 31 04:00:00 EDT 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100374a048· OSTI ID:6518541

Draper, R B; Fox, M A ^[1]

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1. Univ. of Texas, Austin (USA)

Diffuse reflectance flash photolysis has been used to study the kinetics of (SCN){sub 2}{sup {sm bullet}{minus}} decomposition in aqueous suspensions of titanium dioxide (Degussa P-25). (SCN){sub 2}{sup {sm bullet}{minus}} is formed when SCN{sup {sm bullet}}, from oxidation of thiocyanate, SCN{sup {minus}}, by photoexcited TiO{sub 2}, reacts with excess SCN{sup {minus}}. The transient absorption spectra of (SCN){sub 2}{sup {sm bullet}{minus}} obtained on transparent colloidal TiO{sub 2} or on TiO{sub 2} powder suspended in water have maxima at 480 nm and similar absorption band shapes. A two-parameter kinetic model, developed by Albery to describe kinetics in several heterogeneous systems, is applied for the first time to diffuse reflectance measurements. The kinetics of (SCN){sub 2}{sup {sm bullet}} decomposition as a function of laser intensity, KSCN concentration, pH, and ionic strength ({mu}) have been investigated by using this model.

• OSTI ID: 6518541
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 94:11; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
ANTITHYROID DRUGS
CARBONIC ACID DERIVATIVES
CHALCOGENIDES
CHEMICAL REACTIONS
DATA
DATA ANALYSIS
DECOMPOSITION
DRUGS
EXPERIMENTAL DATA
HORMONE ANTAGONISTS
INFORMATION
MEASURING INSTRUMENTS
MEASURING METHODS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
THIOCYANATES
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS