Polymer-assisted Crystallization and Defect Passivation in Planar Wide Bandgap FAPbBr3 Perovskite Solar Cells

S1 Supporting Information: Polymer-assisted Crystallization and Defect Passivation in Planar Wide Bandgap FAPbBr3 Perovskite Solar Cells Amalraj Peter Amalathas1,2*, Loheeswaran Selvadurai1,3, Lucie Landová2,4, Neda Neykova2,4 and Jakub Holovský2,4* 1Department of Physics, Faculty of Science, University of Jaffna, Jaffna 40000, Sri Lanka 2Centre for Advanced Photovoltaics, Faculty of Electrical Engineering, Czech Technical University in Prague, Technick 2, 166 27 Prague, Czech Republic 3Department of Physical Science, Trincomalee Campus, Eastern University, Trincomalee 31010, Sri Lanka 4 Institute of Physics, Czech Academy of Sciences, v. v. i., Cukrovarnick 10, 162 00 Prague, Czech Republic *Corresponding authors: [email protected]; [email protected] S2 Figure S1: (a) UV–Vis absorbance spectra of FAPbBr3 films with and without PMMA treatment and (b, c) Tauc plots used to estimate the optical bandgap (Eg), showing Eg ≈ 2.28 eV for both samples. Figure S2: Extraction of Urbach energy (Eu) from PDS spectra for (a) untreated and (b) PMMAtreated FAPbBr3 films, demonstrating reduced energetic disorder upon PMMA incorporation. S3 The carrier lifetime is obtained by fitting the PL transient decays with a bi-exponential decay function as follows 𝑓(𝑡)= 𝐴1𝑒𝑥𝑝(− 𝑡 𝜏1)+ 𝐴2𝑒𝑥𝑝(− 𝑡 𝜏2)+ 𝐵 where A1 and A2 represent the time-independent decay amplitudes, B is a constant, and τ1 and τ2 are the fast and slow decay time, respectively. The weighted-average lifetime (τavg) is calculated from the fit curve parameters according to the following equation. 𝜏𝑎𝑣𝑔 =𝐴1𝜏12+ 𝐴2𝜏22 𝐴1𝜏1+ 𝐴2𝜏2 Table S1. Summary of the fit and calculated parameters of the TRPL spectra of the FAPbBr3 perovskite films prepared without and with PMMA anti-solvent treatment. Sample name A1(%) τ1 (ns) A2(%) τ2 (ns) Average τ (ns) FAPbBr3 83.40 5.88 16.60 41.95 27.05 FAPbBr3-PMMA 77.40 8.30 22.60 51.07 35.78 S4 Figure S3: Space-charge-limited current (SCLC) measurements of electron-only devices fabricated with (a) untreated and (b) PMMA-treated FAPbBr3 films, showing trap-filled limit voltages (VTFL) and calculated trap densities (Nt). S5 Figure S4: The external quantum efficiency (EQE) spectra and integrated JSC for the best performing the FAPbBr3 perovskite solar cells prepared without and with PMMA anti-solvent treatment. S6 Figure S5: Statistical distribution box plots of (a)Voc, (b) Jsc and (c)FF for the FAPbBr3 perovskite solar cells prepared without and with PMMA anti-solvent treatment. S7 Table S2: Summary of the average photovoltaic parameters of the FAPbBr3 perovskite solar cells prepared without and with PMMA anti-solvent treatment. Name Voc (V) Jsc(mA/cm2) FF(%) PCE(%) FAPbBr3 1.354 ± 0.040 7.60 ± 0.21 48.1 ± 4.4 4.95 ± 0.55 FAPbBr3-PMMA 1.468 ± 0.028 7.63 ± 0.23 55.1 ± 3.1 6.16 ± 0.31 S8 Figure S6: Current density-voltage (J-V) curves under reverse and forward scans the FAPbBr3 perovskite solar cells prepared without and with PMMA anti-solvent treatment. S9 Table S3: Summary of the photovoltaic parameters of reverse and forward scans for the best performing FAPbBr3 perovskite solar cells prepared without and with PMMA anti-solvent treatment. Name Voc (V) Jsc (mA/cm2) FF (%) PCE(%) H-Index (%) FAPbBr3:Reverse 1.395 7.79 51.3 5.57 13.8 % FAPbBr3:Forward 1.302 7.59 48.6 4.80 FAPbBr3-PMMA: Reverse 1.510 7.75 55.4 6.48 5.1 % FAPbBr3-PMMA: Forward 1.486 7.71 53.7 6.15