Strain-induced rubidium incorporation into wide-bandgap perovskites reduces photovoltage loss
A-site cation mixing can enhance the photovoltaic performance of a wide-bandgap (WBG) perovskite, but rubidium (Rb) cation mixing generally forms a nonperovskite phase. We report that lattice strain locks Rb ions into the α-phase of the lattice of a triple-halide WBG perovskite, preventing phase segregation into a nonperovskite Rb-cesium–rich phase. This process cooperates with chloride accommodation and promotes halide homogenization across the entire film volume. The resulting 1.67–electron volt WBG perovskite exhibits photoluminescence quantum yields exceeding 14% under 1-sun-equivalent irradiation, corresponding to a quasi–Fermi level splitting of ~1.34 electron volts. A WBG perovskite solar cell with an open-circuit voltage ( V OC ) of 1.30 volts was prepared, corresponding to 93.5% of the radiative V OC limit and representing the lowest photovoltage loss relative to the theoretical limit observed in WBG perovskites.
École Polytechnique Fédérale de Lausanne
Department of Materials Science and Engineering, National University of Singapore, Singapore.
École Polytechnique Fédérale de Lausanne
École Polytechnique Fédérale de Lausanne
School of Energy and Power Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, PR China.
École Polytechnique Fédérale de Lausanne
École Polytechnique Fédérale de Lausanne
École Polytechnique Fédérale de Lausanne
École Polytechnique Fédérale de Lausanne
École Polytechnique Fédérale de Lausanne
2025-04-04
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EPFL