Aggregative Luminescence from Perovskite Precursors

In this work, we conducted a detailed investigation into the optical properties of all-inorganic perovskite (CsPbBr3) precursors. The absorption, photoluminescence (PL), and photoluminescence excitation spectra of the precursors were analyzed in a broad concentration and various solvents. In specific solvents (such as DMSO, DMF, and NMP), the CsPbBr3 precursor gradually transformed from solution into a colloid and exhibited aggregation-induced emission (AIE) as the concentration increased, and the luminescence intensity and color of the colloid could be controlled by changing the solvent and precursor ratio. Understanding the optoelectronic properties of the precursor may provide deeper insight into the mechanisms that govern the formation and crystallization processes of perovskites, which is vital for the solution-process device performance. Besides, we discussed the difference between the aggregates in the organic system (such as TPE) and the inorganic system (such as CsPbBr3).