2, Chonbuk National University, Jeonju, , Korea (the Republic of)
As organic-inorganic lead halide perovskite emerges as a potential emissive material for light-emitting devices such as light emitting diodes (LEDs) and lasers, the necessity of understanding its fundamental emission characteristics is being emphasized. In general, the temperature-dependent photoluminescence of the material comprises fruitful photo-physical information such as phonon scattering, activation energy for the radiative recombination of the excitons etc. In this study, we report on the temperature-dependent emission properties of three different types of CH3NH3PbBr3 perovskite: single crystal, quantum dots and polycrystalline thin films. The evolution of emission peaks for every photoluminescence spectra shows continuous blue shift with increasing temperature from 20 to 300 K, except when the phase transition appears as sudden red shift in certain temperature range (~120 K) for single crystal. The photo-physical properties such as exciton binding energy and exciton-phonon scattering were also investigated for different types of CH3NH3PbBr3 perovskite samples. Among three types of CH3NH3PbBr3 perovskite, quantum dots show lower phonon scattering with higher exciton binding energy that ensure better emission property for their use in light emitting applications, especially, LEDs.