Polyoxometalate-CdS quantum dots co-sensitized TiO2 nanorods array: enhanced charge separation and light to electricity conversion efficiency

The first example of polyoxometalate (POM)-CdS quantum dots co-sensitized solar cell was successfully constructed via the chemical bath deposition and successive ionic layer adsorption method. The introduction of POM molecules not only successfully realizes a strong coupling of the different nanoparticles, but also enhances the electron transfer among the components of the nanohybrids. When assembled into solar cell devices, the as-grown CdS quantum dots/POM/TiO2 nanorods films are superior in charge separation as well as carrier transport, thus achieving higher short circuit current, fill factor and final conversion efficiency than the common CdS nanocrystal shell on TiO2 nanorods.