Understanding the Degradation of Methylenediammonium and Its Role in Phase-Stabilizing Formamidinium Lead Triiodide.

Autor: Duijnstee EA; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Gallant BM; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Holzhey P; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Kubicki DJ; Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom., Collavini S; POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018 Donostia-San Sebastián, Spain., Sturdza BK; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Sansom HC; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Smith J; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Gutmann MJ; ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 0QX,United Kingdom., Saha S; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Gedda M; King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal 23955-6900, Saudi Arabia., Nugraha MI; King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal 23955-6900, Saudi Arabia.; Research Center for Advanced Materials, National Research and Innovation Agency (BRIN), South Tangerang 15314, Banten, Indonesia., Kober-Czerny M; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Xia C; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Wright AD; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Lin YH; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Ramadan AJ; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.; Department of Physics and Astronomy, The University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH, United Kingdom., Matzen A; Department of Earth Sciences, University of Oxford, 3 South Parks Road, Oxford OX1 3AN, United Kingdom., Hung EY; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Seo S; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Zhou S; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Lim J; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.; Graduate School of Energy Science and Technology (GEST), Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea., Anthopoulos TD; King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal 23955-6900, Saudi Arabia., Filip MR; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Johnston MB; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Nicholas RJ; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom., Delgado JL; POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018 Donostia-San Sebastián, Spain.; Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain., Snaith HJ; Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
Jazyk: angličtina
Zdroj: Journal of the American Chemical Society [J Am Chem Soc] 2023 May 10; Vol. 145 (18), pp. 10275-10284. Date of Electronic Publication: 2023 Apr 28.
DOI: 10.1021/jacs.3c01531
Abstrakt: Formamidinium lead triiodide (FAPbI 3 ) is the leading candidate for single-junction metal-halide perovskite photovoltaics, despite the metastability of this phase. To enhance its ambient-phase stability and produce world-record photovoltaic efficiencies, methylenediammonium dichloride (MDACl 2 ) has been used as an additive in FAPbI 3 . MDA 2+ has been reported as incorporated into the perovskite lattice alongside Cl - . However, the precise function and role of MDA 2+ remain uncertain. Here, we grow FAPbI 3 single crystals from a solution containing MDACl 2 (FAPbI 3 -M). We demonstrate that FAPbI 3 -M crystals are stable against transformation to the photoinactive δ-phase for more than one year under ambient conditions. Critically, we reveal that MDA 2+ is not the direct cause of the enhanced material stability. Instead, MDA 2+ degrades rapidly to produce ammonium and methaniminium, which subsequently oligomerizes to yield hexamethylenetetramine (HMTA). FAPbI 3 crystals grown from a solution containing HMTA (FAPbI 3 -H) replicate the enhanced α-phase stability of FAPbI 3 -M. However, we further determine that HMTA is unstable in the perovskite precursor solution, where reaction with FA + is possible, leading instead to the formation of tetrahydrotriazinium (THTZ-H + ). By a combination of liquid- and solid-state NMR techniques, we show that THTZ-H + is selectively incorporated into the bulk of both FAPbI 3 -M and FAPbI 3 -H at ∼0.5 mol % and infer that this addition is responsible for the improved α-phase stability.
Databáze: MEDLINE