Dual passivation in air for constructing high-efficiency wide-bandgap perovskite solar cell modules

Abstract

Wide-bandgap perovskites (WB-PVKs) are highly promising materials for tandem photovoltaic applications, yet their practical performance is significantly hindered by critical issues such as non-radiative recombination and photo-induced phase segregation. Herein, we report a dual-passivation strategy utilizing phenylethylammonium chloride (PEACl) and 1,3-diaminopropane dihydroiodide (PDADI) to simultaneously enhance crystallinity and reduce defect density in 1.68 eV WB-PVK films. The passivation layers were fabricated via a scalable doctor-blading technique under ambient conditions, achieving power conversion efficiencies exceeding 16% over a large active area of 64.624 cm2. PEACl and PDADI together reduced surface defects, suppressed 2D-phase formation, and increased grain size from 450 to 850 nm. Moreover, the defect density at the perovskite/electron transport layer interface decreased by approximately 27%, leading to a notable enhancement in device efficiency from ∼15% up to a maximum of 16.05%. These results demonstrate that the developed dual-passivation method effectively addresses both photovoltaic performance and phase stability issues, providing a scalable and industrially viable approach toward the fabrication of high-efficiency wide-bandgap perovskite solar modules.