Layer-dependent structure-optoelectronic property relationships for two-dimensional ruddlesden-popper phase (BA)2Csn−1PbnBr3n+1 perovskites

Recently, hybrid two-dimensional (2D) Ruddlesden-Popper (RP) phase layered halide perovskite structures of (BA)2Csn-1PbnBr3n+1 (BA is the butylammonium organic chain and n is the number of inorganic perovskite-like layers) have been experimental synthesized and indicated superior optical properties. Here, we reported an investigation of the above series of layered halide perovskites (n = 1, 2, 3 and ∞). Their structural, electronic and optical properties were calculated using first-principle approaches, including the bond angles, band structures, formation energy, carrier effective masses, density of states, differential charge densities, Bader charge analysis, optical absorption spectra and transition dipole moment. As a consequence of these findings, with the increase in the number of inorganic layers, perovskite materials showed lower bandgaps, improved light absorption and poorer stability. Hence, tuning the inorganic layer thickness of layered 2D RP phase perovskites is a suitable method to enhance their optoelectronic properties. This work provides a theoretical basis for layered 2D perovskite materials with large-scale and low-cost applications in the photoluminescent device light-emitting diodes.