Enhanced Photovoltaic Performances in Dye-Sensitized Solar Cells

This work demonstrated improvements in the photovoltaic performance metrics of a dye-sensitized solar cell (DSSC) through the application of Eu-doped strontium silicate (Sr2SiO4:Eu3+), a luminescent downshifting (LDS) material. The material converted underutilized high-energy ultraviolet (UV) photons into lower-energy visible photons for better spectral responsivity in the DSSC. A conventional solid-state technique was applied in the synthesis of the material. Surface morphology was examined by scanning electron microscopy (SEM). Photoluminescence (PL) measurements were conducted to analyze fluorescence emission. The photovoltaic performances of the bare and LDS-enhanced devices were analyzed using photovoltaic current–voltage measurements. Compared to the bare DSSC, the cell containing Sr2SiO4:Eu3+ LDS phosphor material had an enhancement of 14.8% in the short-circuit current density (Jsc), from 0.243–0.279 mA/cm2. The open-circuit voltage (Voc) yielded an improvement of 10% from 580–638 mV. Maximum power output (Pmax) produced a boost of 26.5% from 0.0136–0.0172 mW and the efficiency improvement at 26.6% from 1.09–1.38%. The coefficient of variation was introduced to evaluate device reproducibility. The device with the incorporation of Sr2SiO4:Eu3+ LDS phosphor depicted a coefficient of variation of 8.5%, suggesting good DSSC reproducibility.