High-Efficiency Perovskite/Silicon Tandem Solar Cells Based on Wide-Bandgap Perovskite Solar Cells with Unprecedented Fill Factor

Abstract

By mixing 2PACz and Me-4PACz, an energetically homogeneous buried interface is formed, enabling preferential energy alignment at the hole transport layer/perovskite (1.67 eV) interface, which delivers a certified fill factor of 86.8% and a power conversion efficiency of 23.42%. Simulations indicate that at lower interface defect densities (1 × 108–1 × 1011 cm−2), improvements in FF dominate the device performance, whereas at higher defect densities (1 × 1012–1 × 1013 cm−2), Voc is the key factor.