A hierarchical shell locks and stabilizes perovskite nanocrystals with near-unity quantum yield

초록

INTRODUCTION: Luminescent materials have powered advances in various applications, including displays, lighting, sensing, imaging, and optical communication. Solid-state light emitters must exhibit both strong absorption and high photoluminescence quantum yield (PLQY) to maximize light-conversion efficiency. However, almost all known emitters exhibit concentration-induced quenching and self-absorption when integrated into dense solid films, fundamentally limiting external quantum yield (EQY; PLQY × absorptance) and light-conversion efficiency. Consequently, more than 2000 terawatt-hours of electricity are wasted annually in lighting and display technologies because of suboptimal electro-optical conversion, corresponding to ~8% of global electricity consumption. Colloidal perovskite nanocrystals (PeNCs) possess high absorption coefficients and intrinsically high PLQY, making them promising light-conversion materials. Yet their soft ionic lattices and labile surfaces undergo light-, heat-, and moisture-induced structural and chemical degradation. Achieving near-unity PLQY with commercially viable stability remains a central challenge. RATIONALE: Recent findings in bulk perovskites indicated that photo- or thermal-induced lattice expansion softens the crystal lattice and accelerates defect formation. However, how this lattice-softening couples with surface reactions in colloidal PeNC solids has remained unclear. We identify that PeNC degradation proceeds through a lattice-interface interlinked pathway, in which lattice expansion weakens ionic bonding, enhances ion migration, and facilitates surface oxidation and hydration reactions. Therefore, a stabilization strategy must simultaneously lock the lattice and chemically stabilize the surface rather than act only as a passive barrier. RESULTS: We introduce a hierarchical shell (HS) composed of interbonded PbSO₄-SiO₂-siloxane layers. This structure forms a lattice-interface interlocking network that locks the ionic lattice and stabilizes surface chemistry. HS inorganic PeNC (HS-CsPbBr₃) films show a time for 10% PLQY loss (T₉₀) of 3211 hours at 60°C, 90% relative humidity (RH) and 12,000 hours under continuous blue-light illumination, indicating long-term stability relevant for potential commercial applications. The HS strategy is composition-ally general and scalable, enabling stable emission across 409 to 783 nm, including mixed-halide and hybrid perovskite formulations. Furthermore, HS organic-inorganic hybrid PeNC (HS-MAPbBr₃) showing pure-green emission, a composition that is typically highly vulnerable to moisture and heat, exhibits extended humid-thermal and photostability lifetimes, surpassing T₉₀ = 3900 hours and estimated T₉₀ = 27,234 hours, respectively. HS-MAPbBr₃ PeNC films also achieve 100.0% PLQY (average 98.6%), turning self-absorption into efficient photon recycling. A 20 wt % HS-MAPbBr₃ film achieves EQY = 91.4%, approaching the theoretical limit and surpassing previously reported solid-state emitters. The HS structure prevents lead leakage and supports roll-to-roll coating, inkjet printing, and >3500 pixels per inch photolithographic patterning for high-resolution display demonstrations. CONCLUSION: The HS provides an interbonded stabilization framework that locks the lattice and stabilizes the interface, suppressing the lattice-interface interlinked degradation pathway. This approach enables near-unity PLQY, converts reabsorption into photon recycling, and achieves photoluminescence stability compatible with commercial use. Owing to broad compositional compatibility and patterning scalability, HS-PeNCs are well-suited for large-area displays (such as 75-inch televisions), mid-size tablets (~10 inch), and high-resolution microdisplays for augmented- and virtual-reality systems, as well as for solid-state lighting and bio-optoelectronic modules (for example, photoplethysmography sensing). More broadly, the lattice-interface interlocking concept provides a generalizable stabilization strategy for halide perovskite materials and related optoelectronic devices. © © 2026 the authors, some rights reserved.

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