Tunable fluorescence and optical nonlinearities of all inorganic colloidal cesium lead halide perovskite nanocrystals

The formation of cesium lead halide perovskite nanocrystals are very effortless due to its extremely fast reaction kinetics. Herein, we present simple hot-inject approach and anion exchange reaction to fabricate all inorganic colloidal CsPbX 3 perovskite nanocrystals (NCs). The colloidal CsPbX 3 NCs with controlling-size exhibit the characteristics of the high luminescent intensity, superior quantum yields (QY, above 69%) and the narrow-band emission tuning, the bandgap energies and emission spectra are readily tunable over the entire visible spectral region of 425–710 nm. Moreover, the third-order nonlinear optical properties of all inorganic colloidal perovskite nanocrystals (CsPbCl 3 , CsPbBr 3 , CsPbI 3 ) were measured using the Z-scan technique, indicating excellent third-order optical nonlinearities. Nonlinear optical susceptibilities reaching to 3.78 × 10 −11  esu for CsPbBr 3 NCs, figure of merit is achieving above 5 for CsPbI 3 NCs. These interesting results demonstrate that the as-prepared all inorganic colloidal CsPbX 3 perovskite nanocrystals are expected to hold great promise for application on nonlinear optoelectronic devices .