Efficient and Stable Tandem Solar Cells With Conformal Solution‐Processed Perovskite on Fully Textured Silicon

Abstract Conformal deposition of perovskite on fully textured silicon bottom cells using low‐cost solution processing remains challenging, limiting the process compatibility and power conversion efficiency (PCE) of perovskite/silicon tandem solar cells. Herein, this challenge through synergetic engineering of the perovskite composition and tunneling recombination junction (TRJ) is addressed. The utilization of wide bandgap perovskite with high cesium content and silicon heterojunction (SHJ) bottom cell with hydrogenated nanocrystalline silicon (nc‐Si:H) TRJ is found to enable conformal perovskite on fully textured SHJ bottom cells using solution processing. A remarkable PCE of 33.38% (certified 32.94%) is achieved for the tandem, featuring a record short‐circuit current density of 21.21 mA cm −2 . The tandem displays excellent stability, retaining 80% of its initial efficiency after 2324 h of operation at maximum power point (AM 1.5G, 25 °C).