PbS Quantum Dots Embedded in a ZnS Dielectric Matrix for Bulk Heterojunction Solar Cell Applications

We demonstrate a novel bulk heterojunction structure based on a mesoporous TiO2 substrate, PbS quantum dots (QDs), and a ZnS dielectric medium. The galena PbS QD arrays embedded in an amorphous ZnS matrix are adopted to fill up the mesoporous TiO2 electrode with an in situ approach, i.e., successive ionic layer adsorption and reaction. The inorganic ZnS resembles the capping material normally used in colloidal QDs to control the size of PbS.