Impact of Hydrogen Vacancies on Non‐Radiative Recombination in Metal‐Halide Perovskites

Abstract Hydrogen vacancies (V H ) were considered major non‐radiative recombination centers in hybrid perovskites. By employing a multiscale approach that combines first‐principles calculations and molecular dynamics (MDs) simulations, our findings indicated that the V H impact was overestimated due to the previous metastable V H configurations. The organic molecules with V H located on either the nitrogen or carbon atom act as the ligands that form energetically stable dimers with Pb 2+ cations. These dimers lower V H energy by 0.35–0.97 eV in MAPbI 3 and by 0.88–1.01 eV in FAPbI 3 , compared to non‐bonding configurations. These dimers significantly boosted potential energy barriers of hole capture, resulting in a dramatic reduction in carrier capture coefficients by over 10 orders of magnitude. Consequently, the total capture coefficients ( C total ) for the dominant V H in MAPbI 3 and FAPbI 3 are on the order of 10 −17 and 10 −31 cm −3 s −1 , respectively. By uncovering the negligible impact of V H on non‐radiative recombination, this work shifts the focus toward more significant defects, for instance, iodine interstitial (with a capture coefficient on the order of 10 −8 cm −3 s −1 ), thereby paving the way for optimizing perovskite solar cells efficiency to meet the Shockley–Queisser limit.