Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Environmental photochemistry on surfaces. Charge injection from excited fulvic acid into semiconductor colloids

Journal Article · · Environmental Science and Technology; (United States)
DOI:https://doi.org/10.1021/es00034a013· OSTI ID:6718477
 [1];  [2]
  1. Indiana Univ. Northwest, Gary, IN (United States)
  2. Univ. of Notre Dame, Notre Dame, IN (United States)

The ability of naturally occurring fulvic acid to sensitize a large band-gap semiconductor, colloidal ZnO, has been investigated by fluorescence emission and transient absorption measurements in a mixed alcohol-water system. The fulvic acid strongly adsorbs on the semiconductor particles, with an apparent association constant of 12000 [+-] 500 M[sup [minus]1]. The net charge-transfer efficiency as determined by the fluorescence quenching of reference Suwanee River fulvic acid (SFA) by ZnO was 73%. The laser flash photolysis experiments that elucidate the mechanistic details of the charge injection from excited fulvic acid into the conduction band of ZnO (k[sub et] = 6.8 x 10[sup 8] s[sup [minus]1]) are described. 28 refs., 5 figs.

OSTI ID:
6718477
Journal Information:
Environmental Science and Technology; (United States), Journal Name: Environmental Science and Technology; (United States) Vol. 26:10; ISSN ESTHAG; ISSN 0013-936X
Country of Publication:
United States
Language:
English