Structural and optical properties of ionic liquid-based hybrid perovskitoid: A combined experimental and theoretical investigation

Herein, we report a novel layered lead bromide, (CH₃CH₂)₃N+Br−(CH₂)₂NH₃⁺)PbBr₃, where bulky organic cations, (CH₃CH₂)₃N+Br−(CH₂)₂NH₃⁺), amino-ethyl triethyl ammonium [aetriea] were not only incorporated between the inorganic layers but also sandwiched within the inorganic [PbBr₆]⁴− octahedral layered structure. The UV-Visible, photoluminescence spectroscopy (PL), X-ray diffraction (XRD) and a field-emission scanning electron microscope (FE-SEM) result show that the new perovskitoid has a microrod shape with an estimated bandgap of ~3.05 eV. The structural and optoelectronic properties of the [aetriea]PbBr₃ perovskitoid were further corroborated by first-principles density functional theory (DFT) calculations. Thermogravimetric analysis (TGA) data show good stability of the [aetriea]PbBr₃ perovskitoid. Time-resolved photoluminescence (TRPL) decays from new [aetriea]PbBr₃perovskitoid showing 6 ns average lifetime. These results suggest that doubly charged cation hybrid perovskite materials are potential candidates for optoelectronic applications.