Long afterglow Sr4Al14O25:Eu,Dy phosphors as both scattering and down converting layer for CdS quantum dot-sensitized solar cells

Abstract

Long afterglow Sr₄Al₁₄O₂₅:Eu,Dy phosphors were introduced into the TiO₂ photoanode of CdS quantum dot-sensitized solar cells (QDSSCs) as both a scattering and down converting layer, and the photovoltaic performances of the cells were investigated. The results show that the cell with Sr₄Al₁₄O₂₅:Eu,Dy achieves a power conversion efficiency of 1.40%, which is an increase of 38% compared to the cell without Sr₄Al₁₄O₂₅:Eu,Dy (1.02%). The performance improvement is attributed to enhanced light harvesting via improved light absorption and scattering processes. After a single sun illumination for 1 min and subsequent removal of the light source, the cell with Sr₄Al₁₄O₂₅:Eu,Dy could be driven even in the dark by the long persistent light from Sr₄Al₁₄O₂₅:Eu,Dy.