Polymer ligands induced remarkable spectral shifts in all-inorganic lead halide perovskite nanocrystals

Perovskite nanocrystals (NCs) have aroused wide interest in the field of optoelectronics. Herein, a quantitative post-processing method is proposed to precisely alter the photoluminescence of lead halide perovskite NCs by ligand substitution using a multidentate multifunctional polymer ligand with amide, carboxylic acid and terminal double bond groups. Surprisingly, the synergistic effect of the ligand leads to a continuously blue-shifted emission over a wide visible region (∼100 nm) with increasing addition of the polymer ligand. Moreover, the full width at half maximum (fwhm) also gradually narrows, indicating the formation of a uniform particle size after the ligand surface interaction. Simultaneously, the terminal double bonds can be cross-linked with styrene to protect perovskite NCs from moisture. These results provide a new route for controllable photoluminescence regulation and preliminarily explore the correlation between the luminescence properties of perovskite NCs and polymer ligands.