Quasi-2D lead-free halide perovskite using superalkali cations for red-light-emitting diodes

Two dimensional halide perovskites have attracted intense attention, but there is no study to consider quasi-2D lead-free perovskites with superalkali cations as potential emitting materials. Herein, the quasi-2D [C6H5(CH2)2NH3]2H5O2Sn2Br7 perovskite is systematically studied by using ab initio molecular dynamics simulation and first principles calculations. The calculated results show that the quasi-2D perovskite has negative formation energy, small effective hole and electron masses, stable dynamics performance, suitable exciton binding energy and direct band gap, and H5O2 superalkali cations that don’t agglomerated. Moreover, the band-edge states do not change for the quasi-2D perovskite after ab initio molecular dynamics simulation of 3 ps. Overall, our results indicated that the quasi-2D [C6H5(CH2)2NH3]2H5O2Sn2Br7 perovskite may be applied to red-light-emitting diodes.