A universal strategy toward homogenized metal oxide/perovskite contact for efficient solar cells and modules fabricated in ambient air

Ambient-air fabrication of perovskite solar cells (PSCs) offers substantial advantages for scalable commercialization. However, ambient moisture promotes the formation of undesirable DMSO-based adducts that deteriorate perovskite (PVK) film crystallinity and lead to poor interfacial contact, particularly at the buried interface with the metal oxide (MO) charge transport layer, thereby compromising the device efficiency and stability. Here, we report a universal strategy employing hydrazide additives to effectively suppress DMSO-based adducts by competitively coordinating with perovskite precursors, while simultaneously binding strongly with both the MO and PVK through Lewis acid–base interactions and hydrogen bonding. These interactions promote the removal of residual DMSO at the MO/PVK interface, leading to high-quality perovskite films with homogenized MO/PVK contact across a wide humidity range in ambient air and dual-side passivation that effectively suppresses interfacial recombination losses. As a result, the best-performing PSCs deliver power conversion efficiencies (PCEs) of 25.07% and 24.75% for the SnO₂-based regular and NiO_x-based inverted architectures, respectively, representing >15% improvement over the reference devices. Notably, this homogenized MO/PVK contact is achieved without additional interfacial treatment, making it ideally suited for scalable device fabrication, as demonstrated by the mini perovskite solar modules (PSMs, 4.6 cm × 4.6 cm) attaining PCEs of 22.65% (regular) and 21.73% (inverted). The devices also show excellent operational stability under maximum power point tracking (MPPT) and enhanced resistance to light, thermal, and humidity stress according to ISOS protocols. Additionally, this strategy shows excellent compatibility with the blade-coating technique, highlighting its strong potential for large-area PSM production.