Efficiency enhancement of silicon solar cells through a downshifting and antireflective oxysulfide phosphor layer

A simple, rapid, and low-cost anti-reflection coating (ARC) for polycrystalline silicon (pc-Si) solar cells has been developed by spin coating a solution of submicron spherical Gd2O2S:Eu3+ phosphor impregnated in a polyvinylpyrrolidone (PVP) matrix on the textured surface of the solar cell. Under a simulated one-sun illumination, this predesigned device achieved an enhancement of 6.74 mA/cm2 in short-circuit current density and 2.76% in power conversion efficiency relative to those for a pristine cell. Based on photoluminescence, reflectance, and optical spectral studies, the underlying mechanism for these improvements can be attributed to the luminescent down-shifting (LDS) capability in the ultraviolet range and additional promotion of light absorption within the measured spectral region. Our results indicate that a suitable inorganic phosphor impregnated in a polymer matrix may potentially serve as a feasible solution to compensate for the spectral mismatch and Fresnel reflection loss of silicon solar cells.