Nanostructures for enhanced electronic performance

In this section, we turn our attention to the second lever for improving the performance of a photovoltaic cell mentioned in the previous section: increasing the amount of charge collected once photons have been absorbed into the material.

Just as metal nanoparticles can be added to generate plasmonic effects and improve light trapping, other types of non-metallic nanoparticles can also be used to enhance electronic performance. We're talking here about quantum dots, which correspond to semiconductor nanoparticles 2 to 10 nm in diameter. At these nanometric scales, the gap energy of the semiconductor material becomes dependent on the size of the nanoparticle, making it possible to generate electron-hole pairs at energy levels in areas where thin- or thick-film silicon would be ineffective. Hybrid solar cells have thus been designed, with quantum dots transferring...