Metal halide perovskite nanorods with tailored dimensions, compositions and stabilities

The colloidal synthesis of one-dimensional metal halide perovskite nanocrystals with precisely controlled diameter (D) and length (L) values is challenging due to the intrinsic structural symmetry and ionic crystal nature of the perovskites. This hinders investigation into their size- and shape-dependent properties and prevents their application. Here we report a general platform of cylindrical unimolecular nanoreactors to synthesize a library of one-dimensional perovskite nanorods (NRs) with tailored dimensions (D approximate to 7-16 nm; L approximate to 40-220 nm), compositions (all-inorganic perovskites; organic-inorganic perovskites; lead-free double perovskites) and enhanced colloidal, photo, polar-solvent and thermal stabilities. The dependence of the charge-carrier dynamics, photoluminescence quantum yield and optical anisotropy of the perovskite NRs on the diameter and length was examined. Decreasing the diameter yields opposite trends in the photoluminescence quantum yields and charge-carrier dynamics to that of increasing the length. In addition, enhanced structural anisotropy (that is, a higher aspect ratio of L/D) always increases the optical anisotropy of the perovskite NRs. By leveraging the cylindrical unimolecules as nanoreactors, a rich variety of uniform perovskite NRs with controllable dimensions, compositions and enhanced stabilities can be designed for use as building blocks for a variety of applications, such as in optoelectronic devices, catalysis and sensors. Controllable synthesis of 1D metal halide perovskite nanocrystals is challenging due to their structural symmetry and ionic crystal nature. Now, a general platform of cylindrical unimolecular nanoreactors has been developed to craft a variety of 1D perovskite nanorods with tailored dimensions and compositions.