Enhancement of photoconversion efficiency of CdSe quantum dots sensitized Al doped ZnO/Si heterojunction device decorated with Ag nanostructures

In this work, CdSe/ZnS QDs decorated Ag nanoparticles (Ag NPs) have been deposited on Si/AZO heterojunction to promote the absorption capability and external quantum efficiency (EQE) of the solar cell. To understand the individual plasmonic effect of Ag NPs and CdSe/ZnS QDs on Si/AZO heterojunction solar cell, Si/AZO, Si/AZO/Ag-NPs, and Si/AZO/Ag-NPs/QDs device structures have been fabricated. The optical enhancement of photocurrent and photoluminescence (PL) can be attributed to higher photo-conversion efficiency due to plasmon-enhanced light harvesting. The absorbance and PL emission peak have been enhanced up to ∼4.6 and 2.1 times for CdSe/ZnS QDs decorated Ag NPs at 478 nm and 610 nm, respectively. In addition, absorption gain improved by 1.13 times compared to the individual gain of Ag NPs or CdSe/ZnS QDs. Present work elucidates a novel approach of incorporating CdSe/ZnS QDs decorated Ag NPs to promote photo-conversion of solar energy, an urgent requirement in photovoltaics and optoelectronic devices.