Ion-exchange-induced MAPbI3 thin-film 3D-2D and 3D-1D conversions: unveiling structural transformations in films via synergistic and competitive approaches

作者：Chen, Shuhuang; Zhang, Jie^*; Piao, Jinhua; Fu, Zhiyong^*

来源：New Journal of Chemistry, 2021, 45(16): 7103-7108.

DOI：10.1039/d1nj00810b

The gas-induced transformation of organic-inorganic halide perovskites shows unprecedented phenomena and applications in the area of optoelectronics. In this study, the chemical origins of the gas-induced dimensional transformation (GIDT) of MAPbI(3) have been investigated within CH3NH2 (MA), CH3(CH2)(5)NH2 (C6) and (CH3CH2)(3)N (C6') atmospheres. With the exposure of the as-synthesized MAPbI(3) perovskite thin film to the C6 gas, the rapid displacement of the MA(+) cations by the C6(+) cations is achieved, thus inducing the MAPbI(3) thin film structure to turn from a three-dimensional motif to two-dimensional (CH3(CH2)(5) NH3)(2)PbI4. By comparison, no response is observed when the same process is carried out in the presence of the tertiary amine C6' gas. With MA acting as a coinduction conversion agent, the MAPbI(3) film transfers to a quasi-2D perovskite structure within MA and C6 mixture atmosphere, while it changes to a one-dimensional (C6H15NH)PbI3 chain as MA combines with the C6' gas, showing an effective mixed amine strategy for GIDT. Interestingly, the obtained quasi-2D perovskite films display tuneable absorption and emission luminescent characters associated with the volume ratios of MA/C6-mixed amines.