Design the π-stacking type of perovskite-like iodobismuthates to enhance their optoelectronic properties

One-dimension (1D) or two-dimension (2D) iodobismuthates are promising perovskite-like photoactive materials for electronic devices. Many researchers focused on how to qualitatively build frameworks to increase the dimension of charge transformation due to the construction of connectivity between bismuth halide ions as the key to achieve ideal properties. In this context, two kinds of organic amine compounds, benzylamine and N-methylaniline, were well-designed and corresponding iodobismuthates single crystals: BA(3)Bi(2)I(9) and NMA(3)Bi(2)I(9) (BA = C6H5CH2NH3+, NMA = C6H5(CH3)NH2+) were prepared by solvent evaporation process. Their crystals characterized by S-XRD, SEM, etc. After thoroughly investigated their structures, optical and electronic properties, the results show that the space group changed from C2/c (BABI) to P2(1)/c (NMABI) due to the pi-stacking type shifted from I-type to Z-type. So as to the reconstruction of their band structures and the C 2p of BABI is more closed to the band edge than that of NMABI revealed by density functional theory (DFT). Although BABI has higher electrical resistivity, higher trap-state density and lower carrier mobility, its optoelectronic property is superior to NMABI as a result of the I-type pi-stacking increased the electronic dimensionality. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

One-dimensional or two-dimensional iodobismuthates are promising perovskite-like photoactive materials for electronic devices. Researchers focused on building frameworks to increase the dimension of charge transformation in order to achieve ideal properties. The properties of the materials were investigated and compared, showing that the electronic dimensionality was increased in one case due to a certain type of pi-stacking, leading to superior optoelectronic properties.