ArticleMaterials SciencePlasmon-enhanced photocurrent generation in quantum dots-sensitized solar cells by coupling of gold nanocrystals

The noble metal nanoparticles, such as gold, silver and copper, has been widely incorporated into the photoelectronic devices acting as a light-harvesting antenna and enhancing photocurrents through their light scattering or localized surface plasmon resonance effects. Here, this article presented the investigations into the use of gold nanocrystals to realize the plasmon-enhanced photocurrent generation in TiO2 nanorod-based quantum dots-sensitized solar cells (QDSSCs). By introducing the gold nanocrystals, the short-circuit current density (Jsc) of QDSSCs was enhanced more than 10% from 7.788 to 8.574 mA/cm2 due to the direct injection of hot electrons from the gold nanocrystals to the photoanode. In order to confirm such conclusion, composite Au/TiO2 nanostructure was also fabricated. Indeed, the hot electrons injection resulted photocurrent density of ∼5 mA/cm2 was clearly observed under the visible light irradiation.