Enhanced conversion efficiency of crystalline Si solar cells via luminescent down-shifting using Ba2SiO4 : Eu2+ phosphor

Abstract

The colloidal submicron needle-like Ba2SiO4 : Eu2+ phosphor coated on microtextured silicon surface has been used as a luminescent down-shifting (LDS) material for enhancing the power conversion efficiency of solar cells. Under a simulated one-sun illumination, upon phosphor coating the solar cells showed an enhancement of the short-circuit current density (J(sc)) increased from 34.00 to 34.48 mA/cm(2), meanwhile the power conversion efficiency (PCE) was enhanced from 15.13% to 15.36%. The related underlying mechanism for these enhancements can be attributed to photon down-shifting and light scattering effect through the investigation of PLE spectrum, reflectance, and external quantum efficiency. Our results indicate that the colloidal submicron needle-like Ba2SiO4 : Eu2+ phosphor not only act as LDS centers in the UV region but also serve as an antireflection coating for enhancing the light absorption in the visible regime.