ABSTRACT Photo-activities at Inorganic/Organic/Interfaces (IOI) consisting of CdS/ Polyterthiophine (PTTh) assemblies were investigated in nanoparticle suspension and in thin solid film forms. The effects PTTh modifier cause on the photoelec-trochemical behavior of the IOI were investigated using [Fe(CN)6]4- as photoactive hydrated electron donor agent. Results show that the adsorption process of [Fe(CN)6]3- (photolysis product) control the photoactivity outcome of IOI assemblies. CdS/PTTh shows lower heterogeneous photochemical response than native CdS. Native CdS amorphous nanoparticles adsorb more [Fe(CN)6]3- with very steady adsorption /desorption process than the modified ones. The interface activities were explained by analyzing the IOI junctions’ characteristics, such as electron affinity, work function and hole/electrons barrier heights. The aqueous nano-systems retained moderate stability as indicated by the reproducibility of their photocatalytic activities. Both [Fe(CN)6]4- and PTTh contributed to the stability of native CdS surfaces.
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