Revealing the internal luminescence quantum efficiency of perovskite films via accurate quantification of photon recycling

•Novel curve-fitting model reveals real internal luminescence quantum efficiency•Scattering of initially trapped photons strongly increases their escape probability•Effect photon recycling in perovskite films has previously been overestimated•New benchmark for the efficiency 78% Metal halide perovskites are a promising candidate next-generation solar cells. In order to approach theoretical limit, it is paramount importance maximize (Qilum), which measure optoelectronic quality semiconductors. This work introduces novel that, first time, allows researchers accurately determine Qilum under illumination conditions. Applying CH3NH3PbI3 films, have among highest external efficiencies reported date, corrects previous coarse estimates ?90% new ?78%. there much more room future material optimization than thought. The implications our results on state-of-the-art cells will spark further improvements toward limit make them viable solution green energy. (Qilum) provides an excellent assessment To from experimentally accessible (Qelum), essential account recycling, and this requires knowledge probability (p¯e). Here, we establish analysis procedure based that determines p¯e photoluminescence (PL) spectra measured with confocal microscope integrating sphere setup. We show scattering-induced outcoupling PL explains commonly observed red-shifted broadened spectral shapes leads being factor two higher compared earlier assumptions. exceptionally high Qelum up 47.4% 78.0% ± 0.5%. Thereby, study beyond scope reducing non-radiative recombination power conversion (PCE) (PSCs) reached certified 25.5%.1NREL Best Research-Cell Efficiency Chart.https://www.nrel.gov/pv/cell-efficiency.htmlDate: 2020Google Scholar Further advance PCE fundamental ?30.5% (for [MAPI] bandgap ?1.61 eV2Pazos-Outón L.M. Xiao T.P. Yablonovitch E. Fundamental lead iodide cells.J. Phys. Chem. 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