Photocatalytic properties of poly(3-octylthiophene-2,5-diyl) film blended with sensitizer for the degradation of iprobenfos fungicide

The fluorescence behaviors of poly(3-octylthiophene-2,5-diyl) (POTh) contai ning photosensitizers such as perylene (Per) and 9-cyanoanthracence (CNA) a nd the degradation of iprobenfos fungicide by the POTh film blended with Pe r were investigated. The fluorescence intensity of POTh was enhanced by the addition of Per whereas it was not apparently exhibited when using CNA. Th e degradation rate of iprobenfos was examined under the conditions of bubbl ing O-2 and visible light irradiation. The rate was accelerated by blending Per and/or N,N,N',N'-tetramethylbenzidine (TMB) which is a cation scavenge r with the POTh film. A photosensitizing process involving energy and/or el ectron transfer from excited Per to POTh and efficient charge separation ga ve an appropriate explanation for the accelerated degradation of iprobenfos , together with the process that we have previously reported for the degrad ation of iprobenfos by OH radical formed on the POTh film. The POTh film bl ended with Per and TMB was stable even after 100 h irradiation. (C) 2000 El sevier Science B.V. All rights reserved.