Graded bandgap structure for PbS/CdS/ZnS quantum-dot-sensitized solar cells with a PbxCd1−xS interlayer

Abstract

To suppress the electron-hole recombination in the multishell sensitizer for quantum-dot-sensitized solar cells (QDSCs), the PbxCd1−xS interlayer is incorporated between the PbS core and CdS shell. The PbS/PbxCd1−xS/CdS structure enhances the cell efficiency by ∼60% compared to PbS/CdS QDSCs, and consequently shows a power-conversion efficiency of 1.37% with ZnS coating. Open-circuit voltage decay confirmed that the PbxCd1−xS interlayer effectively reduces the recombination at the PbS/CdS interface. Furthermore, with respect to the peak shift of incident photon-to-current conversion efficiency, the interlayer also increases the light-harvesting efficiency in the higher-wavelength region by reducing the exciton confinement within the PbS sensitizer.

Tailoring band structure of ternary CdS Se1− quantum dots for highly efficient sensitized solar cells

“…That is, a ladder-like energy structure suitable for carrier transfer is attained with the incorporation of CdSSe interlayer. Secondly, different from dye molecules, there exist unwanted interfacial defects at the contact interface between QD sensitizers, especially for that of multilayered QDs, which may inevitably be prone to interphase strain between different QD layers [42,43]. As illustrated in panel (b), in comparison with CdS/CdSe, reduced defects and interphase strain between CdS core and CdSe shell layers should be attained for the CdS/CdSSe/CdSe structure, in which the incorporated CdSSe interlayer Table 3 Photovoltaic parameters of CdSe, CdS/CdSe and CdS/CdSSe/CdSe QDSCs.…”

Facile Conversion Synthesis of Densely-Formed Branched ZnO-Nanowire Arrays for Quantum-Dot-Sensitized Solar Cells

“…For the counter electrode, Ti was deposited on the pre-drilled FTO substrates as adhesion layer, and Cu was deposited by rf magnetron sputtering. The Cudeposited films were sulfurized in a polysulfide solution [23], and thermoplastic foil (60 mm: Dupont) was used as a spacer.…”

Organic-acid texturing of transparent electrodes toward broadband light trapping in thin-film solar cells

“…For enhancing the power-conversion efficiency, much research has been focused on the light trapping to fully utilize broadband light with minimum optical losses [10][11][12][13]. Novel light-trapping methods using photonic structures or plasmonic effects are being continuously reported [14,15].…”