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

Article abstract of DOI:10.1016/j.jallcom.2017.06.034

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 CsPbX₃ perovskite nanocrystals (NCs). The colloidal CsPbX₃ 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 (CsPbCl₃, CsPbBr₃, CsPbI₃) were measured using the Z-scan technique, indicating excellent third-order optical nonlinearities. Nonlinear optical susceptibilities reaching to 3.78 × 10^?11 esu for CsPbBr₃ NCs, figure of merit is achieving above 5 for CsPbI₃ NCs. These interesting results demonstrate that the as-prepared all inorganic colloidal CsPbX₃ perovskite nanocrystals are expected to hold great promise for application on nonlinear optoelectronic devices.