Synergistic Modulation of SnO ₂ and Perovskite Improving the Performance of n–i–p Wide-Band-Gap Perovskite Solar Cells

High Resolution Image Download MS PowerPoint Slide Tin dioxide (SnO 2 ) has emerged as a highly promising candidate for electron transport layers in perovskite solar cells. However, defects in the SnO 2 film and at the interface between SnO 2 and perovskite often cause serious nonradiative recombination, resulting in the deterioration of the performance of perovskite solar cells. Herein, a synergistic passivation strategy is employed through the introduction of amphiphilic fluorosurfactants (FS-31) into the SnO 2 precursor solution, enabling the passivation of defects present both in the SnO 2 film and at the interface between SnO 2 and perovskite. Moreover, FS-31 is capable of modulating the energy level of the SnO 2 film and enhancing the crystalline quality of the wide-band-gap perovskite, thereby minimizing residual lead iodide. Thanks to the positive effects of FS-31, the n–i–p type wide-band-gap perovskite (1.68 eV) solar cells achieve a champion power conversion efficiency (PCE) of 20.92%, an open circuit voltage ( V OC ) of 1.24 V, and a minimal V OC deficit of 0.44 V. Furthermore, this simple strategy provides strong support for the preparation of high-efficiency n–i–p perovskite/silicon tandem solar cells.