Surface Octahedra Isolation Treatment Enables Silicon-Rivaling Outdoor Stability in Industrial-Scale Perovskite Solar Modules
Perovskite solar cells (PSCs) have achieved a record power conversion efficiency (PCE) of 27.0%, rivaling silicon-based cells while halving cost, positioning them near commercialization. However, long-term outdoor stability of industrial-scale perovskite solar modules (PSMs) remains a critical challenge. Guo et al. report a milestone: an industrial-scale PSM (aperture area 785 cm2) with a PCE of 19.6% and projected T80 (time to 80% of initial PCE) exceeding 6.7 years under light-dark cycling. The PSM demonstrated stability comparable to commercial silicon solar cells during 45 days of outdoor operation. The key innovation is perovskite surface reconstruction via vapor-deposited terpyridine (Tpy), which reorganizes defective [PbI6]4− octahedra into a zero-dimensional (0D) structure with fully isolated octahedra, eliminating irreversible ion migration. Grazing-incident wide-angle X-ray scattering confirmed formation of (Tpy)2PbI6 on the surface. Time-of-flight secondary-ion mass spectrometry showed that the 0D layer confines iodine migration, making it reversible during light-dark cycles, whereas pristine films exhibit irreversible migration. Temperature-dependent conductivity revealed increased activation energy for ion migration from 0.43 to 0.68 eV. The treated films exhibited photoluminescence lifetime of 532.6 ns and trap density of 1.57×10^15 cm−3. Small-area devices (0.16 cm2) achieved PCE of 25.3%, while scaled modules (785 cm2) retained 19.6%, a new world record. This surface isolation treatment offers a scalable route to stabilize large-area PSMs for outdoor deployment.