Enhancement of photovoltaic performance of TiO₂-based dye-sensitized solar cells by doping Ca₃La₃₍₁₋ₓ₎Eu₃ₓ(BO₃)₅

A series of Ca₃La₃₍₁₋ₓ₎Eu₃ₓ(BO₃)₅ (CLBO:3xEu³⁺) phosphors were prepared by the Pechini-type sol–gel technique. Rietveld refinement was performed using the powder X-ray diffraction data, which shows the occupation of Eu³⁺ on both Ca²⁺ and La³⁺ sites with a preferred location on the La³⁺ site over the Ca²⁺ site. In order to enhance the photovoltaic performance of dye-sensitized solar cells (DSSCs), a novel design is demonstrated by introducing CLBO:3xEu³⁺ in TiO₂-based DSSC. As a new conversion luminescence medium, CLBO:3xEu³⁺ transfers ultraviolet light to visible light via down-conversion, and increases the solar light harvest and photocurrent of DSSC. The experimental results reveal the feasibility of the conversion luminescence by doping rare-earth phosphors in the DSSC, providing an effective novel method to improve the sunlight conversion efficiency for solar cells.