Abstract
The immobilization on a semiconductor surface of a bis(indolyl)maleimide functionalized with two carboxylic acid groups by alkylation of the indole nitrogen atoms is presented and its synthesis is described. The compound, 3,4-bis[1-(carboxymethyl)-3-indolyl]-1H-pyrrole-2,5-dione is strongly colored and emissive and the imide part can coordinate an oxidizable substrate. Its absorption and emission ...
Abstract
The immobilization on a semiconductor surface of a bis(indolyl)maleimide functionalized with two carboxylic acid groups by alkylation of the indole nitrogen atoms is presented and its synthesis is described. The compound, 3,4-bis[1-(carboxymethyl)-3-indolyl]-1H-pyrrole-2,5-dione is strongly colored and emissive and the imide part can coordinate an oxidizable substrate. Its absorption and emission spectra on TiO2 are substantially changed as compared to the spectra obtained in neat acetonitrile, indicating surface bonding through the carboxy groups. The quenching of the fluorescence of the sensitizer by the TiO2 surface is almost complete, reflecting the high degree of association between the TiO2 and the dye, fast charge injection and good electronic coupling between the sensitizer and the semiconductor.