Tuning photophysical properties of semiconducting polymer nanoparticles for improved photocatalytic activity

This study investigates the relation between the optical and structural properties of poly(3-hexylthiophene) nanoparticles with their efficiency as photocatalysts for the degradation of water pollutants. Two nanoparticle preparation methods were investigated. Our results indicate that nanoparticles prepared by the miniemulsion method are more efficient in inducing photodegradation. The higher crystallinity, observed by X-ray scattering experiments and the presence of surfactant in these nanoparticles affect the photophysical properties. The fluorescence lifetime of miniemulsion nanoparticles is shorter than that of nanoparticles prepared by the flash method, favoring charge transfer towards the surface of the nanoparticle. These charges, in the presence of water, produce highly reactive oxygen species, responsible for the pollutant photodegradation.