γ-Cyclodextrin-mediated buried interface engineering for high-performance and stable perovskite solar cells.

γ-Cyclodextrin (γ-CD), a bowl-shaped supramolecule with abundant peripheral hydroxyl groups, is introduced as a bifunctional passivator for the buried SnO2/perovskite interface, enabling bilateral defect passivation and suppressed non-radiative recombination. The modified devices deliver a champion power conversion efficiency of 24.61% (0.09 cm2) and exhibit significantly enhanced long-term stability.