Influence of A-site cation on the thermal stability of metal halide perovskite polycrystalline films

This paper reports a comparative study of thermal stability between all-organic metal halide perovskite (MHP) CsPbBr3 and organic–inorganic hybrid MHP (methylammonium lead bromide MAPbBr3). The film morphology, crystal structure, steady-state photoluminescence intensity, and photoluminescence lifetime of CsPbBr3 and MAPbBr3 polycrystalline films were measured after thermal annealing at temperatures from 70°C to 230°C. The CsPbBr3 films exhibited little change in their structural and luminescent properties after being annealed even at 230°C, whereas the MAPbBr3 films exhibited a significant change in such properties due to their decomposition into PbBr2 when annealed at ≥180°C. This study increased the understanding of the difference in the thermal stability of MHP polycrystalline films with different A-site cations.