25.91%‐Efficiency and Durable Inverted Perovskite Solar Cells Enabled by a Multifunctional Molecule Mediated Precursor Engineering

The stability of the precursor is essential for producing high-quality perovskite films with minimal non-radiative recombination. In this study, methionine sulfoxide (MTSO), which features multiple electron-donation sites, is strategically chosen as a precursor stabilizer and crystal growth mediator for inverted perovskite solar cells (PSCs). MTSO stabilizes the precursor by inhibiting the oxidation of iodide ions and passivates charged traps through coordination and hydrogen bonding interactions. This leads to enhanced crystallinity, reduced non-radiative recombination, and decreased internal residual stress in perovskite film. As a result, remarkable power conversion efficiencies of 25.91% (certified 25.76%) with a minimal voltage deficit of 0.36 V for a 0.09-cm