Origin of High Efficiency and Long-Term Stability in Ionic Liquid Perovskite Photovoltaic
Perovskite precursor solution chemistry. (a) The solution images of the MAPbI3 perovskite precursor dissolved in different IL solvents. (b) The solution images of different perovskite precursors (MA-, FA-, and Cs-based perovskites) dissolved in the MAAc solvent. (c) The Pb -edge XANES spectra of the DMF and MAAc perovskite precursors. The -weighted Fourier transforms of the EXAFS spectra at the Pb -edge for the (d) MAAc and (e) DMF perovskite precursors. (f) 1H NMR spectra of a pure MAAc solvent and different perovskite precursors in the MAAc solvent.