Metal halide perovskites (MHPs), as emerging optoelectronic materials for photovoltaic devices (PVs), light-emitting diodes (LEDs), and photodetectors, have demonstrated remarkable potential for breakthrough developments. Despite these advances, the long-term operational stability, a persistent challenge across all perovskite-based optoelectronic applications, continues to impede their rapid commercialization. For perovskite solar cell, combined light and thermal stress represent the dominant intrinsic degradation factors, while failures related to oxygen and humidity have been largely mitigated through encapsulation^[1].

Increasing evidence suggests that the early-stage performance collapse is not associated with the deterioration of charge generation dynamics or the formation of deep electronic traps, as long as the perovskite maintains its structural and compositional integrity. It appears that charge transport and extraction are the limiting factors that need to be resolved within the entire photovoltaic conversion pathway.

Here, we demonstrate two distinct modes of collapse in the charge transport and extraction processes during aging: a “bias-sensitive mode” (Me-4PACz-based cells) and a “bias-independent mode” (PTAA-based cells). Mechanistic studies reveal a direct correlation between charge/ion dynamics under different bias conditions and material evolution, highlighting the critical roles of ion redistribution and interfacial charge accumulation in governing device stability.

Based on these insights, we developed interfacial strategies targeting both charge-transport interfaces. At the bottom interface, a solvent-vapor-annealed small-molecule/polymer blended hole transport layer (Blend_SVA) was introduced to suppress mobile-ion generation and mitigate field screening. This approach significantly enhanced long-term operational stability under continuous full-spectrum illumination at 70 ± 5 °C and open-circuit conditions, achieving average and champion T80 lifetimes of 1,370 h and 1,570 h, respectively. At the top interface, amino-silane passivation molecules (AEAPTMS) effectively preserved perovskite crystallinity, suppressed non-radiative recombination, and extended device durability, with average and champion T80 values of approximately 1,100 h and 1,600 h under the same aging conditions^[2]. When both interfacial strategies were combined, the resulting perovskite solar cells exhibited remarkable post–burn-in stability, with average and champion T80 lifetimes of 2,839 h and 4,358 h under identical stress conditions.

This work elucidates interfacial dynamics underlying degradation and presents design guidelines toward stable perovskite optoelectronics.