| Source: |
Chang, X, Liu, Y, Ping, Y, Wu, N, Yang, T, Tian, C, Ling, Z, Vishal, B, Pininti, A R, Park, J B, Jeong, S Y, Qin, Y, Hui, W T, Yeung, F S Y, Yang, Y-Y, Liao, H, Prasetio, A, Isikgor, F H, He, M, Utomo, D S, Wang, R, Zhao, K, Lanza, M, Woo, H Y, Heeney, M, De Wolf, S, Lin, Y-H, Tsetseris, L, Azmi, R & Anthopoulos, T D 2026, 'Multivalent ligands regulate dimensional engineering for inverted perovskite solar modules', Science, vol. 391, no. 6781, pp. 153-159. https://doi.org/10.1126/science.aea0656 |
| Description: |
Multivalent, resonance-stabilized amidinium ligands enable stronger chemical coordination and reduced deprotonation compared with conventional monovalent ammonium ligands in low-dimensional perovskites. Here, we introduce a controllable one- to two-dimensional (1D-to-2D) structural transition strategy by systematically tuning ligand conformation, thereby modulating hydrogen bonding, π–π stacking, and basicity to elucidate the relationship between molecular structure, interfacial interactions, and resulting dimensionality. The 1D-amidinium perovskite structure, with its pronounced geometric anisotropy, impedes uniform surface coverage and defect passivation. In contrast, the 2D-amidinium perovskite forms a continuous, homogeneous interfacial layer, enabling more effective defect passivation and favorable energy-level alignment. With dimensionality control, inverted 3D/2D-amidinium perovskite solar cells deliver 25.4% power conversion efficiency (1.1 square centimeters, steady-state certified) and maintain >95% of their initial efficiency after 1100 hours of continuous 1-sun operation at 85°C. |