Time-resolved spectroscopic study of resonant energy transfer between lead-sulphide quantum dots and bulk silicon

The brightness, large absorption cross-section and flexibility of colloidal nanocrystal quantum-dots (QDs) make these materials promising candidates for light harvesting applications. The difficulty of efficiently extracting photogenerated carriers from the QDs however drastically limits the power conversion efficiency of NQD solar cells. A possible way to circumvent these issues is to engineer hybrid devices that utilize alternative energy transfer schemes to effectively separate light harvesting and charge extraction in different materials. In this context, hybrid bulk semiconductor/QDs devices coupled through near-field resonant energy transfer offer a promising route towards low cost ultra-thin photovoltaics. In this work, we demonstrate non-radiative resonance energy transfer between lead sulphide (PbS) QDs and bulk silicon using time-resolved spectroscopy.