Doctor-Blade Printing Bilayer Silica for Broadband Antireflection in Perovskite Solar Cells

Light reflection arising from the contrast of the refractive index in multilayered solar cells leads to low energy conversion efficiency and strong angular dependence of photovoltaic performance. Herein, a bilayer antireflection coating (ARC) with a gradual increase of refractive index was constructed and deposited atop glass via a fast doctor-blade printing technique. The averaged transmittance of the ARC coated glass substrate was significantly increased by 4.3% in a broad wavelength range from 400 to 1200 nm, resulting in an efficiency enhancement of perovskite solar cells. Moreover, the nanostructured ARCs effectively suppressed angular dependence of the device performance and endowed a promising self-cleaning property.