Nanophotonic-structured front contact for high-performance perovskite solar cells

We report the design of a nanophotonic metal-oxide front contact aimed at perovskite solar cells (PSCs) to enhance optoelectronic properties and device stability in the presence of ultraviolet (UV) light. High-quality Cr-doped ZnO film was prepared by industrially feasible magnetron sputter deposition for the electron transport layer of PSCs. As a means, the influence of the Cr content on the film and device was systematically determined. In-depth device optics and electrical effects were studied using advanced three-dimensional opto-electrical multiphysics rigorous simulations, optimizing the front contact for realizing high performance. The numerical simulation was validated by fabricating PSCs optimized to reach high performance, energy conversion efficiency (ECE) = 17.3%, open-circuit voltage (V_OC) = 1.08 V, short-circuit current density (J_SC) = 21.1 mA cm⁻², and fill-factor (FF) = 76%. Finally, a realistic front contact of nanophotonic architecture was proposed while improving broadband light absorption of the solar spectrum and light harvesting, resulting in enhanced quantum efficiency (QE). The nanophotonic PSC enables J_SC improvement by ∼17% while reducing the reflection by 12%, resulting in an estimated conversion efficiency over 23%. It is further demonstrated how the PSCs’ UV-stability can be improved without considerably sacrificing optoelectronic performances. Particulars of nanophotonic designed ZnO:Cr front contact, PSCs device, and fabrication process are described. [Figure not available: see fulltext.].